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Efficacy of Spirulina Extract Plus Zinc in Patients of Chronic Arsenic Poisoning: A Randomized Placebo-Controlled Study

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Millions of people in Bangladesh, India, Taiwan, and Chile are consuming high concentration of arsenic through drinking water, and thousands of them have already developed chronic arsenic poisoning. There is no specific treatment. Some authors suggest the use of vitamins and minerals for more than 6 months. The present placebo-controlled double-blind study was conducted to evaluate effectiveness of spirulina extract plus zinc in the treatment of chronic arsenic poisoning. Forty-one patients of chronic arsenic poisoning were randomly treated orally by either placebo (17 patients) or spirulina extract (250 mg) plus zinc (2 mg) (24 patients) twice daily for 16 weeks. Each patient was supplied with arsenic-safe drinking water by installing a locally made water filter at household level. Effectiveness of spirulina extract plus zinc was evaluated by comparing changes in skin manifestations (clinical scores), arsenic contents in urine and hair, between the placebo- and spirulina extract plus zinc-treated groups. The concentrations of total arsenic in water (without filtration) of placebo- and spirulina extract plus zinc-treated groups were 150.1 +/- 18.3 and 161.7 +/- 23.9 microg/l, respectively. Intake of these high concentrations of arsenic lead to increased excretion of arsenic in urine (72.1 +/- 14.5 microg/l in placebo-treated group and 78.4 +/- 19.1 microg/l in spirulina plus zinc-treated group). After 2 weeks of using filtered water, there were significant reduction of both arsenic intake through water and urinary arsenic excretion (8.3 +/- 3.6 microg/l and 18.4 +/- 7.3 microg/l in placebo group; 9.7 +/- 5.4 microg/l and 21.6 +/- 5.8 microg/l) in spirulina extract plus zinc-treated group. There was a sharp increase in urinary excretion of arsenic (138 +/- 43.6 microg/l) at 4 weeks following spirulina plus zinc administration and the effect was continued for another 2 weeks. Spirulina extract plus zinc removed 47.1% arsenic from scalp hair. Spirulina extract had no major adverse effect that required physician's attention. The clinical scores (median) for melanosis before and after treatment with placebo was not statistically significant (p > 0.05), whereas in spirulina extract plus zinc-treated group it was statistically significant (p < 0.01). In cases of keratosis, the median clinical scores before and after treatment was not statistically significant (p > 0.05) in placebo-treated group. In spirulina extract plus zinc-treated group, the clinical scores for keratosis before and after treatment was statistically significant (p < 0.05). Results show that spirulina extract (250 mg) plus zinc (2 mg) twice daily for 16 weeks may be useful for the treatment of chronic arsenic poisoning with melanosis and keratosis.
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128
The clinical Toxicology, 44: 1-7, 2006
Efficacy of Spirulina Extract plus zinc in Patients of
chronic arsenic
Poisoning: A Randomized Placebo-
Controlled Study
Mir Misbahuddin
Department of Pharmacology.
Bangabandhu Sheikh Mujib Medical University.
Dhaka, Bangladesh.
AZM Maidul Islam
Department of Dermatology and Venereology,
Bangabamdhu Sheikh Mujib Medical University,
Dhaka, Bangladesh.
Salamat Khandker and Ifthaker-Al-Mahmud
WHO Arsenic Project.
Dhaka. Bangladesh
Nazrul Islam and Anjumanara
Department of Pharmacology.
Bangabandhu Sheikh Mijib Medical University
Dhaka. Bangladesh.
Background. Millions of people in Bangladesh, India, Taiwan, and
Chile are consuming high concentration of arsenic through drinking
water. And thousands of them have already developed chronic
arsenic poisoning. There is no specific treatment. Some authors
suggest the use of vitamins and minerals for more than 6 months The
present placebo-controlled doble-blind study was conducted to
evaluate effectiveness of spirulina extract plus zinc in the treatment
of chronic arsenic poisoning, Methods, Forty-one patients of chronic
arsenic poisoning were randomly treated orally by either placebo (17
patients) or spirulina extract (250 mg) plus zinc (2 mg) (24 patients)
twice daily for 16 weeks. Each patient was supplied with arsenic-
safe drinking water by installing a locally made water filter at
household level. Effectiveness of spirulina extract plus zinc was
evaluated by comparing changes in skin manifestations (clinical
scores). Arsenic contents in urine and hair, between the placebo- and
spirulina extract plus zinc-treated group. Results. The concentrations
of total arsenic in water (without filtration) of placebo- and spirulina
extract plus zinc-treated groups were 150.1 ± 18.3 and 161.7 ± 23.9
µg/1, respectively, Intake of these high concentrations of arsenic
11
Evaluation of physical and mental development
lead to increased excretion of these high concentrations of arsenic
lead to increased excretion of arsenic in urine (72.1 ± 14.5 µg /1 in
placebo-treated group and 78.4 ± 19.1 µg/1 in spirulina plus zinc-
treated group). Sgyrt 2 weeks of using filtered water, there were
significant reduction of both arsenic intake through water and
urinary arsenic excretion (8.3 ± 3.6 µg/1 and 18.4 ± 7.3 µg/1 in placebo group; 9.7
± 5.4 µg/1 and 21.6 ± 5.8 µg/1) in spirulina extract plus zinc treated group, there was
a sharp increase in urinary excretion of arsenic ( 138 ± 43.6 µg/1) at 4 weeks
following spirulina plus zinc administration and the effect was continued for another
2 weeks. Spiraling extract plus zinc removed 47.1% arsenic from scalp hair.
Spiraling extract had nomajor adverse effect that required physimian's attention. The
clinical scores (median) for melanosis before and after treatment with placebo was
not statistically significant (p<0.05). Whereas in spirulina extract plus zinc-treated
group it was statistically significant (p<0.01) In cases of keratosis, the median
clinical scores before and after treatment was not statistically (p>0.05) in placebo-
treated group. In spirulina extract plus zinc-treated group, the clinical score for
keratosis before and after treatment was statistically significant (p<0.05).
Conclusions: Results show that spiraling extract (205mg) plus zinc (2mg) twice
daily for 16 weeks may be useful for the treatment of chronic arsenic poisoning with
melanosis and keratosis.
Evaluation of physical and mental development
Keywords Chronic arsenic poisoning: Spirulina: zinc
Received 8 October 2004: accepted 8 June 2005
Address correspondence to prof. Mir Misbahuddin. Department of
Pharmacology, Bangabandlu Sheikh Mujib Medical University. Dhaka. Bangladesh.
E-mail: mmisbah@ aitlbd.net
BACKGROUND
In 1993. Bangladeshi people realized that they were exposed to high concentrations
of inorganic arsenic (more than 50 ppb) through drinking water (1). Shallow
tubewells are the main source of drinking water and surveys show that shallow
tubwells in 59 out of 64 districts has been contaminated with various degrees of
arsenic concentration. The Total population (57 million) is consuming arsenic (2).
More than 30.000 people have already developed the signs and symptoms of chronic
arsenic poisoning. Involvement of skin is the first manifestation, characterized by
areas of hyper pigmentation on the upper chest and arms. keratosis develops later on
at the palms and soles with fissures, cracks and warty lesions. Chronic arsenic
exposure induces cardiovascular diseases, developmental abnormalities, neurologic
and neurobehavioral disorders. diabetes. hearing loss. hematological disorders. and
various types of eancer (3.4). Thus, the economy of the patient as well as the nation
will be affected.
Still, there is no specific treatment. After diagnosis, the first step is to stop drinking
arsenic contaminated water and allow the patient to use arsenic-safe water. Chelating
agents, like dimercaprol (BAL),2-3dimercaptopropanesulphonate sodium (DMPS)
and meso-2,3diercaptosuccinic acid (DMSA), are effective in the treatment of acute
arsenic poisoning, but their usefulness is yet to be established in treating chronic
arsenic poisoning (5.6) The beneficial effect of oral supplementation with retirol in
the treatment of cutaneous chronic arsenic poisoning was first described more than
50 years ago (7). More recently. patients with cutaneous aresenicosis who were
treated for 2 to 7 months with oral etretinate, a synthetic aromatic retinoid. showed
clinical and histopathological improvement (8). Combination of vitamins A'E and C
were used to treat the cases of chronic arsenic poisoning (9). Combination of several
vitamins and minerals (beta-carotene, ascorbic acid, alphatocopherol, folic acid, zinc
and selenium) were found to be effective in the removal of tissue arsenic by
increasing its metabolism (10). the use of several antioxidants at a time needs
rationality. At the same time, long duration of treatment up to 12 months may affect
the compliance of the patient, in addition, there is a common belief among the
paticnts that a vitamin is not adrug at all, Combined administration of vitamin C pus,
DMSA, and vitamin E plus monoisoamyl.
DMSA in rats led to a more pronounced depletion of brain arsenic (11). Spirulina. a
filamentous, unicellular alga, is a cyanobactcrium growth in certain countries as
food for human and animal consumption (12). It is a rich source of proteins.
vitamins, amino acids, minerals and other nutrients. Spirulination. was found to be
effective in the removal of arsenic from arsenic-loaded tissues in rats (13).
Subsequently, administration of 10 g of spirulina per day for 3 months was reported
Evaluation of physical and mental development
to be effective in the treatment of chronic arsenic poisoning (14-16). However, these
studies were not scicntifically sound, as no placebo treatment was given, The large
dose of spirulina in powder of tablet form may affect the compliance of the patient,
In addition. it has offensive smell and taste. Zinc is a known antioxidant and is
shown to prevent acute arsenic toxicity in mice (17). Supplementation of Zinc also
reduces the accumulated arsenic from different tissues of rat, following chronic
exposure to arsenic (18).
In the present study we used spirulina extract plus zinc and conducted a double-blind
placebo controlled trial for the treatment of chronic arsenic poisoning. Thus. the
volume of drug will be deereased. offensive smell and taste will be overcome and
thereby the compliance will be good.
SUBJECTS AND METHODS
The study was conducted during July 2003 to July2004 with the approval of the
ethical committee of the Bangladesh Medical Research Council (BMRC).
Study Area
The study was carried out at Muradnagar Upazilla (total arca of 339 Sq. km) of
Comilla District, which is about 110 km sotheast of Dhaka, This upazilla is on of the
high-density populated (total population is 577.971) areas. There are 30.199
tubewells, of which 93.5% are contaminated with a high concentration of arsenic
(more than 50 µg/1). On average 19.14 persons are using the water of one tubewell
for drinking and cooking purpose.
Patients
Patents with skin manifestations (suspected chronic poisoning) were requested by
announcement to attend either the Muradnagar Health Complex, or temporary
Arsenic Camp at Babutipara (within the Upazilla but 16 km away from the
Muradngar Health Complex). to rececive drug treatment, Initially, more than 200
patients responded, of which, 117 patients were finally diagnosed as chronic arsenic
poisoning (confirmed by clinical and laboratory findings). Due to limited funding.
we randomly slected only 50 cases to particpate in the trial.
Patients were, at first, diagnosed clinically based on the skin manifestations of
melanosis and keratosis, A questionnaire was filled out, including information on the
source of drinking water, duration of arsenic exposure, smoking habits. previous
history of taking drugs, etc, Both males and females Were included in thes study ,
The age of the patients ranged from 18 to 58 years, Pregnant women and patients
with hepatic of renal failure, were not included in this study, The history of exposure
to arsenic, and presence of arsenic in urine and/or hair, confirmed the diagnosis.
Each patient visited the Health Complex of Arsenic Camp one every two weeks.
Each time, one acid-washed 20 ml polycthylene container was given to each patient
to collect midstrcam urine at the spot, and another 100 ml bottle to bring filtered
water during the next visit, Hair samples were collected twice (befofe and arter
completion of treatment). About 0.5g of hair (a pencil thickness) was collected from
less readily contaminated sites close to the ocipital area of the scalp (new growth
Evaluation of physical and mental development
hair). Hair longer than I inch from the scalp was excluded, Hair was placed in a
small plastic bag before analysis, Three ml of blood was drawn from the cubital vein
and dept in a small glass vial for transfer to the laboratory, The purpose of the study
was explained to cach patient and requested, him/her to sign a consent form. All the
patients agreed to be included in the trial.
Effectiveness of spirulina was evaluated by clinical improvement by comparing
changes in skin manifestations (clinical seres) and arsenic contents i skin
manifestations (clinical scores) and arsenic contents in urine and haird, between the
placebo- and spirulina extract plus zine treated groups, The total clinical score of the
individual patient of manifestation was estimated by the presence of different
degrees of melanosis (diffuse and rain drop). of kcratosis (diffuse and spotted) in
chcst, abdomen, back, arms, palms, legs and soles, the degree of manifestation was
marked as 0 for mil. I for mild, 2 for mod erate and 3 for severe cases, Thus, the
total score was the sum of marks of manifestation observesd in different parts of an
individual, the estimation of total score was done both before and ater treatment to
compare the effectiveness, Spot urine and hair samples were collected from 10
volunteers of an arsenic unexposed area (Dhaka City) for the estimation of total
arsenic, They were randomly selected after announcement.
Water Filters for Arsenic Removal
Locally made water filters were distrbuted to the selccted patients of chronic arsenic
poisoning (one afilter for each patient ) immcdiately after confirming the diagnosis,
to provide arsenic safe drinking water, Filters were manufactured from the ground
having a single bucket with cover, iron chips and bricks were used to remove arsenic
from arsenic-contaminated drinking water, Each filter was installed into the patient's
house, Each patient was installed how to use the filter properly, and advised to use
that water both for drinking and cooking purposes, to check the amount of arsenic
present in the filtered water, each patient was advised to bring filtered water every to
weeks, The amount of arsenic present in filtered water was mcasured and informed
them at regular interval about their filtered water's arsenic level.
Manufacture of Caplets
At first, spirulina extract was prepared from spirulina flaked, spirulina flakes were
then dried at room temperature and powdered by grinder, one a time, approximately
5kg of spirulina powder was dissolved into 10 liters of 80% ethanol in a glass
container, and kept for 24h. The liquid part of the suspension was separated by a
filter 100 to 200 mesh, The solid part was again suspended in 5 liters of freshly
prepared 80% cthanol for another 48 h. After filtration, all the ethanol extracts were
combined and were filtered by 50 mesh filter paper and was colleeted in a 500 ml
flask, evaporated in a rotary evaorator (40°C) Thus, gren-colored alcohol extract of
spirulina was obtained and washed twice with deionized water, It was finally freeze
dricd and kept at 0°C until the manufacture of caplets The whole extraction process
was performed at room temperature with minimum exposure to light, About 2.0 kg
of spirulina extract was prepared from 25 kg of spirulina flakes. This spirulna extract
was then mixed with zinc and was supplied to a local pharmaceutical company to
Evaluation of physical and mental development
produce caplets. Each caplet contained 250 mg of spirulina extract and 2 mg of zinc.
similar numbers of placebo caplet were prepared using glucose as inert substance,
Both types of caplets had the same sizes, color (yellow colored film coating) and
Smell. Ten caplets were packed in a blister. Packing in blster made the easy
detection of compliance after observing the remnant of the pack following use of
caplets by the patient. Only the code number was printed on cach blister to identify
its content. The disintegration time of each caplet was about 40 min.
Distribution of Drugs
After two weeks of using filtered water, patients were randomly selected from the
list of patients for placebo and spiruling extract plus zinc-treated groups. Each
patient received an envelop containing 28 caplets (drugs for 2 weeks). Each patient
was advised to swallow one caplet twice daily (one in arsenic-safe drinking water
immediately after eating and placing tick marks in the appropriate space printed or
the envelope. The Total duration of treatment was 16 weeks. The patient was
advised either to stop the drug immediately or to contact the local medical officer by
cell phone for necessary measures if he/she felt any adverse effect (s). Each patient
was also advised to keep his/her used blisters, and brought them during the next
visit. The compliance of the paticnt was assessed by counting the number of caplets
used and by examining the tick marks given on the envelope every day, During the
study period patients were advised not to take any other antioxidant (s).
Laboratory Investigations
The amount of total arsenic in the drinking water and urine of 41 patients was
estimated by SDDC (silver diethyldithio carbamate) spectrophotometric method.
Pentavalent arsenic was reduced by potassium iodide. It was then reduced to ars ine
(AsH3) by Zinc in
strong acid solution in an arsine generator. The arsine was then passed through a
scrubber containing glass wool moistened with lead acetate, and into an absorber
tube containing SDDC dissolved in chloroform, The arsine reacted with the silver
salt, forming a soluble red color complex whose absorbance is read in a
spectrophotometer. The maximum absorbance of the resulting color complex Was
taken by a spectrophotometer (Shimazdu. Japan) at 525 nm. The limit of detection
of arsenic in water and urine by this method was 7 µg/1. The hair samples for total
arsenic were estimated by AAS with continuous flowing Hydride Generator (model
210 VGP, Buck Scientific Co, CT, USA). The hair was washed once with acetone
and then sonicatcd in deionized water for 1 min in order to remove the externally
bound arsenic. The hair was dried in an oven, weighed by an electronic balance and
wet digested by acids (nitric acid, sulfuric acid and prerchloric acid) for 2 h. The
remaining volume (about 4 ml) waste constituted to 40 ml with water and an aliquot
was analyzed by AAS. In brief (19): the sample, at first, digested with nitric acid,
sulfuric acid and perchloric acid for 2 h by Bunsen burner. Following digestion, each
sample was introduced into the Hydride Generator by continuous flow of 10%
hydrochloric acid, 3% slfuric acid and 1% sodium brodydride into a gas-lipuid
separator. The arsine vapor produced by arsenic and the hydrogen gas (produced by
Evaluation of physical and mental development
sodium borohydride and acid) was carried by flowing argon gas into a quartz T-tube.
[The tube was heated in an air-acetylene flame, to serve as an atomization cell.] The
current of the Hollow Cathode Lamp for arsenic was 10mA. The wavelength and
spectral bandwidth were 197.7 nm and 0.7 nm, respectively. The limit of detection
was 0.1 µg/g of hair and the precision (within-day variations of replicate
determinations) was 4.5%.
Quality Assurance Procedures
One physician examined all the patients every two weeks without seeing the
patient's file. Another physician wrote the findings without informing the former
physician about previous findings of the patient. Samples were collected using
standard procedures, properly transported and preserved appropriately. Collected
data t the field level were kept under strict confidence until analysis. Samples for
laboratory investigations were coded. 5% of the total samples for arsenic estimation
were validated by another reputed laboratory.
Statistical Analysis
We estimated the significance of difference of clinical scores between the before and
after placebo or spiraling plus zinc-treated groups with the help of the Mann
Whitney test, In the case of the placebo- treated group, the sample size was 17 and
we estimated the value of T using
In the case of spiraling extract plus zinc-treated group, the sample size was 24 and
we computed the data using
Other statistical analyses were carried out using standard software package (SPSS).
st test was also used where necessary. Statistical significance was determined by p
<0.05.
RESULTS
Among the 50 patients, 9(8from the placebo treated group and 1 from the spirulina-
treated group) dropped out due to failure of taking drugs for more than 2 consecutive
weeks (Fig.1). It may be due to no change in improvement of the clinical condition
after taking drugs. Ultimmately,41 patients completed the intake of the drug, of
which 14 were male and 27 were female.
Evaluation of physical and mental development
Among the male patients, 4 received placebo and 10 received spirulina extract plus
zinc. Among the female patientd.13 received placebo and 14 received spirulina
extract plus zinc. In total, 17 patients received placebo and 24 patients received
spirulina extract plus zinc. The mean (±SD) age of placebo-treated group was 35.3
± 8.1 years, whereas spirulina extract plus zinc-treated group was 32.1 ± 12.9 years.
91 % of the patients visited the Health. Complex and Arsenic Camp at Babutipara
personally in order to receive their drugs. Patients' compliance was evaluated.
Intake of the drug by the patients was 98.2% Fourteen patients (36.6%) were
cigarette smokers, and none had a history of drinking alcohol 73.2% patients had a
previous history of taking vitamins of antioxidants for the treatment of chronic
arsenic poisoning. The duration of taking shallow tubewell's water for drinking
purpose was 20.3 ± 11.8 years. Among the 41 patients, 85.4% were using water
from a tube wall for drinking purpose. After the onset of chronic arsenic poisoning,
only 14.6% patients changed their drinking water source from tubewell to either
pond water or rain water.
The arsenic concentrations in tube well water before filtrations of placebo- and
spirulina extract plus zinc-treated groups was 150.1± 18.3 and 161.7 ± 23.9 µg/1,
respectively. The highest concentration of arsenic in tubewell water was 715 µg/1.
The differences between these two groups were not statistically significant. The
water filter was found to be effective to reduce the arsenic level of tube well tater to
8.3 ± 3.6, and 9.7 ± 5.4 µg/1 in placebo- and spirulina extract plus zinc-treated
groups (94.5 and 94.4% removal of arsenic as examined after 2 weeks). But only 3
out of 41 filters (7.3%) provided arsenic safe drinking water throughout the study
period (16 weeks; Fig. 2). The mean duration of effectiveness of the filters was 6.4
weeks.
The duration of suffering from symptoms was 4.8 ± 3.2 years. The highest
percentage of skin manifestation (kurtosis) was found in soles (80.5%). Involvement
of the palm was found in 78% of cases, Mel noses were present in chest. abdomen
and 78% of cases. Mel noses Were present in chest, abdomen and
Evaluation of physical and mental development
back as 68.3, 70.7 and 63.4% of cases, respectively. The maximum score for an
individual was 13 for melanosis and 6 for keratosis. In cases of melanosis, the
median clinical scores before and after treatment with placebo was not statistically
significant (p> 0.05), whereas in spiralina extract plus zinc-treated group it was
statistically significant (p < 0.01). In the case of keratosis, the median clinical scores
before and after treatment was not statistically significant (p>0.05) in the placebo-
treated group. In spirulina extract plus zinc-treated group, it was statistically
significant (p<0.05). Apparent clinical improvements in both melanosis and
keratosis were usually observed after 8-12 weeks,
Six patients experienced tinnitus of both ears immediately after starting drugs (Table
2). Among them, one was male and five were female, This complaint appeared
immediately after starting the drugs and disappeared after 4 to 6 weeks. Other
adverse effects were vertigo, pain in the lower abdomen and headache, The duration
of these complaints were 2 to 8 weeks. The appearance of any adverse effect was
not correlated with the intake of spirulins extract.
The amounts of arsenic in the urine of people not exposed to arsenic were not at
detectable level, whereas patients of chronic arsenic poisoning contained arsenic
72.1 ± 14.5, and 78.4 ± 19.1 µg/1 of urine in placebo- and spirulina extractreated
groups, respectively. After 2 weeks of using arsenic safe drinking water, the
amounts of arsenic excretion in urine was reduceed significantly ( 18.4 ± 7.3 µg/1 in
placebo-treated group and 21.6 ± 5.8 µg/1 in spirulina extractreated group). That is,
there wcre 74.5 and 72.4% dccreascs in arsenic excretion in urineQ, Administration
of spirulina extract plus zinc caused a sharp increase in urinary excretion of arsenic
(138 ± 73.6 µg/1) at 4 weeks (Fig. 3; p<0.05). These increased excretions of arsenic
were not detected after 8 weeks, On the other hand, placebo did not show any
increase in excretion of arsenic hand, placebo did not show any increase in excretion
of arsenic in urine. The differences in arsenic urinary excretion between the tow
groups were not, at least, partially due to differences in renal clearance because the
mean serum creatinin levels of both the groups were within normal range (data not
shown).
Evaluation of physical and mental development
The amounts of arsenic in the hair of 10 individuals from arsenic non-exposed areas
were estimated for comparison, the range of arsenic was 0.05 to 0.034 µg/g. The
amount of arsenic in the hair of placebo- and spirulina extract plus zinc-treated
patients before treatment were 3.08 ± 1.29 and 3.27 ± 1.16 µg/g, respectively
(Fig.4). After 16 weeks treatment, arsenic contents were reduced to 2.99 ± 0.92 in
placebo-treated group, and 1.73 ± 0.68 µg/g in spirulina extract plus zinc-treated
group. Treatment with placebo did not show any significent change, but spirulina
extract plus zinc removed 47.1% arsenic from hair, which was statistically
significant (p<0.05).
TABLE 1
Clinical scores of patients both before and after treatment using mann- Whitney test
Clinical scores (median)
Number of
Patient Patients Calculated T or z value Tabulated T or z value p valuc
Melanosis Placebo 17 T=132.5 T=97 >0.05
Spirulina extract plus zinc 24 Z=3.26 Z=3.29 0.001<p<0.01
Keratosis Placebo 17 T=124.5 T=97 >0.05
Spirulina extract plus zinc 24 Z=2.26 Z.=2.58 0.01<p<0.05
TABLE 2
Adverse effects after administration of placebo and spirulina extract plus zinc containing caplets
Drugs Sex
Spirulina extract
Number of cases Placebo (n=17) Plus zinc (n=24) Male Female
Tinnitus 6 4(23.5) 2(8.3) 1 5
Vertigo 4 3(17.6) 1(4.2) 2 2
Pain in lower 2 1(5.9) 1(4.2) 0 2
abdomen
Headache 1 0(0.0) 1(4.2) 0 1
Data within parenthesis are percentage of patients from each group.
Evaluation of physical and mental development
FIB. 3. Urinary excretion of arsenic in spriulina extract plus zinc-treated parents from 0 to 16
weeks of treatment (0). Data of patients treated with placebo were shown for comparison ()
Data are mean ± S.D. The excretion of arsenic in urine of spirulina treated patients at 4 h was
statistically significant (p<0.05) when compared the placebo group.
DISCUSSION
The present study shows that treatment with spirulina extract plus zinc for 16 weeks
is affective for the clinical improvement of melanosis and keratosis. This treatment
regime was found to be sate, as there was no major adverse affect that required
physician's advice. Effectiveness of spirulina is due to enhanced removal of stored
arsenic, as evidenced by decreased concentration of total arsenic in hair as well as
increased excretion of total arsenic in urine, Intake of toxic levels of arsenic in
drinking water did decrease reduced glutathione (GSH) levels in patients of chronic
arsenic poisoning (20). Our study on rat shows that spirulina increased the level of
GSH in arsenic-loaded liver tissues as well as enhanced the formation of DMA
(Misbahuddin, unpublished data). Like spirulina, antioxidant vitamins are found to
increase the urinary excretion of DMA and MMA (10). Spirulina is adrministered
orally and its effects depend on the extent of absorption. Recently, it was found that
chronic administration of high concentration of arsenic in rats inhibited the
absorption and metabolism of a single dose of therapeutic concentration of
paracetamol (21). This study may raise the need to examine the extent of absorption
and metabolism of spirulina.
Chronic arsenic poisoning is due to chronic administration of high concentration of
arsenic. Immediate stoppage of arsenic contaminated drinking water and the intake
of arsenic safe drinking water are the precondition for the management of chronic
arsenic poisoning. The people of arsenic-affected areas are, at present, fully
Evaluation of physical and mental development
dependent of the shallow tubewell as the source of drinking water. The present study
shows that the water filter used did not provide arsenic safe drinking water
throughout the study period of 16 weeks. The mean duration of effectiveness of the
filters was 6.4 weeks. Rapid deterioration of the effectiveness of the filter may be
due to high phosphate content in water of that area. Spirulina was effective even
after short-term efficacy of the water-filtration system provided to the study
participants. Maximal excretion of arsenic was observed at 4 weeks, but apparent
clinical improvements in both melanosis and keratosis were usually observed after
8.12 weeks. The cause of this delay is not known, but it may be due to failure of
providing arsenic-safe drinking water throughout the study period, However,
spirulina, zinc of a combination would have an imract on the dermal findings that
improved during therapy, without necessarily minimizing arsenic toxicity, but
simply masking it. Simultaneous administration of spirulina and arsenic may reduce
the effective of spirulina, but it does not cause any harmful effect, On the other hand,
treatment with either selenium of zinc in presence of arsenic contaminated drinking
water may increase the accumulation of arsenic in rats (22,23). So, the use of zinc in
humans requires further study because it is very difficuly to provide arsenic-free
drinking water while administering zinc,
ACKNOWLEDGEMENT
This work was supported by a grant from the World Health Organization,
Bangladesh (project no. PHE BAN 003). We gratefully acknowledge the
cooperation of participants in the study. We thank Mr. Han a. Heijanen, Dr. Deoraj
Evaluation of physical and mental development
Caussy and prof. SK. Akhter Ahmad for their helpful comments and criticisms
throughout the course of this study. We thank Prof. Md. Shahidullah for his help in
statistical aspects.
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... The combined antioxidative and immune modulation properties of spirulina helps in the destruction of tumor-forming cells. The extract of spirulina along with zinc is used in the treatment of chronic arsenic poisoning (Misbahuddin et al 2006) [6] . Breast milk is not sufficient for meeting the infant's requirement hence weaning foods should be introduced post 6 months. ...
... The combined antioxidative and immune modulation properties of spirulina helps in the destruction of tumor-forming cells. The extract of spirulina along with zinc is used in the treatment of chronic arsenic poisoning (Misbahuddin et al 2006) [6] . Breast milk is not sufficient for meeting the infant's requirement hence weaning foods should be introduced post 6 months. ...
... The nutritive values were tabulated using calculation method (Indian food composition by ICMR, Longvah et al, 2017) [6] . The following parameters were calculated: calories, carbohydrates, fats, protein, iron, calcium, dietary fiber, phosphorous, beta carotene. ...
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Microalgae are promising sources of biologically active compounds that could be used as functional ingredients. The fascinating properties and healthy chemical composition (high-quality proteins, balanced fatty acid profiles, antioxidants) of spirulina make it a preferred functional ingredient. Spirulina, also known as Arthrospira, is a non-nitrogen-fixing blue-green alga that is edible. With over 30 years of safety research and a long history of healthy human consumption, it complies with all international food safety and quality regulations. An online survey was conducted to understand the consumer's preference and awareness of spirulina and its related products. Multi millet-based weaning food was developed and spirulina was incorporated at 1.5% and 2%. The organoleptic properties of the weaning mix prepared were analyzed by a semi-trained panelist using a 9-point hedonic scale. One-way ANOVA results showed that there was no significant difference between the control and the samples. Also, sample B with 2% spirulina had the maximum overall acceptability. On calculating the nutrient profile of the weaning mix, it was found that the protein content of sample B (2% spirulina) was relatively higher than the control and sample A (1.5% spirulina).
... The most common therapeutic options lead to short-term improvement with recurrence after the stoppage of treatments. The oral formulations studied to treat keratosis are the antioxidants (Yerebakan et al., 2002;Son et al., 2008;Khandker et al., 2006), garlic oil , kala jeera oil (Bashar et al., 2014), spirulina, zinc (Misbahuddin et al., 2006;Rahman et al., 2006) and selenium (Momin et al., 2007;Krohn et al., 2016). ...
... Retinoid (Son et al., 2008), vitamin E (Verret et al., 2005), combination of vitamin A, C and E , folic acid (Gamble et al., 2007), zinc and spirulina (Misbahuddin et al., 2006;Rahman et al., 2006;Misbahuddin and Afrin, 2013), selenium (Momin et al., 2007;Krohn et al., 2016), garlic oil , kala jeera oil (Bashar et al., 2014) and probiotics (Rashid et al., 2014) were tested in several studies to treat arsenicosis. These oral approaches to treatment options are not sign-specific and required a longer time to relieve. ...
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The study was designed to see the effects of tetracycline and clotrimazole on the altered skin flora (Aspergillus and Enterobacter species) in 38 patients with palmar arsenical keratosis. The skin swab and scrapping samples were collected. Tetracycline, clotrimazole and their combination were given as ointment for 3 months. Clotrimazole and tetracycline were found to inhibit the growth of Aspergillus spp. and Enterobacter spp. in vitro. A pH-dependent inhibition of the growth of microorganisms in presence of these antimicrobials was observed, which was highest at pH 8. The percentage reduction of keratotic nodular size was 32.9, 66.1, 61.1 and 32.5 in the groups treated with placebo, tetracycline, clotrimazole and the combination of both, respectively. But none of the interventions was proved statistically significant. No remarkable adverse effect was reported. In conclusion, clotrimazole or tetracycline inhibits the growth of Aspergillus spp. or Enterobacter spp. in vitro. However, there was no statistically significant clinical improvement of the palmar arsenical keratosis.
... Secondly, antioxidant supplement and feeding of As burden reducing agent seem to be beneficial for remedy of arsenicosis (Das and Sengupta, 2008;Khandker et al., 2006). Spirulina (Spirulina platensis), a blue-green alga, possesses antioxidant properties (Bashandy et al., 2016) with corrective properties against heavy metal toxicity, nephrotoxicity induced by heavy metals and drugs and also against cancer, tumor growth and malnutrition (Misbahuddin et al., 2006). Spirulina was also found to attenuate As-induced oxidative stress, testicular damage, and sperm abnormalities by its potent antioxidant activity and maintain the normalcy of the testicular architecture (Bashandy et al., 2016). ...
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Spirulina (Spirulina platensis), has numerous health benefits including antioxidant, immunomodulatory, and anti-inflammatory activities, works against heavy metal toxicity, and is often used as a food supplement in human, animals, birds and fishes. This study aimed to evaluate the protective ability of the dietary spirulina against the toxic effects of inorganic arsenic (iAs) on male reproductive parameters in rats. Seventy-two mature Long-Evans male rats, dividing into six groups (T0, T1, T2, T3, T4 and T5) (12 rats/group) were included in this study. The T3, T4 and T5 group rats were treated with three consecutive doses (1.0 g, 1.5 g and 2.0 g/kg feed) of spirulina in feed along with 3.0 mg NaAsO2/kg body weight (BW) in drinking water (DW) daily for 90 days. Each rat of group T1 received NaAsO2 (3.0 mg/kg BW) in DW, and those of T2 group were fed with spirulina (2.0 g/kg feed) daily for 90 days. The rats of group T0 served as the control with normal feed and water. Total arsenic (tAs) contents, reproductive parameters (testicular weight, sperm motility and morphology), and histological changes in the testicles were evaluated in these rats. Arsenic dosing significantly (p=0.003, Kruskal-Wallis test) increased the tAs contents in the testicles, decreased testes weight, sperm morphology and motility compared to the controls. The effect of arsenic dosing was also evidenced by the histological changes like decreased germinal layers in the seminiferous tubules of the treated rats. Moreover, dietary spirulina (2.0 g/kg feed) supplementation significantly (p=0.011, Kruskal-Wallis test) lowered tAs contents in testicles and increases testes weights, sperm motility and morphology. Therefore, spirulina can be used as an effective dietary supplement to ameliorate the adverse effects of arsenic induced reproductive toxicities. However, further study is required to elucidate the underlying molecular mechanisms of reduction of arsenic induced reproductive toxicity by spirulina.
... Several vitamins and minerals such as vitamin A [2], ascorbic acid [3], alpha-tocopherol [4], zinc [5], folic acid [6], alphalipoic acid [7], and selenium [8] used either alone or in combination were found to be effective in arsenicosis. Some of our foodstuffs such as corn [9], spinach [10], garlic oil [11] and spirulina [12] were proven to relieve the symptoms of arsenicosis. It is still unknown where these compounds act inside the body. ...
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In our quest to find a cure for arsenicosis, an in silico attempt was made to identify a common target for the compounds that relieves the symptoms using Autodock and Discovery studio. Retinol, alpha-tocopherol, ascorbic acid, alpha-lipoic acid and folic acid were used as ligands and an enzyme telomerase reverse transcriptase which was selected as the target protein to search for the structure which had the highest binding affinity with this cancer causing enzyme of the human body. This compound was compared with other potential inhibitors currently under research by docking with 47 important enzymes of the human body found in the protein data bank. Assessment by FAF-Drugs web server showed this compound to be non-toxic. To prove the effectiveness of this drug, both in vivo and in vitro studies are required along with this in silico study.
... [17] Cholesterol bringing down impacts and consequences for diabetes, cardiovascular malady, and stays most significant hazard factors by supplemented with the 4.2 g on day 1 of Spirulina to 15 male volunteers and what's more, in spite of the fact that there was no huge increment in high-thickness lipoprotein (HDL) levels, they watched a huge decrease of high-thickness lipoprotein (LDL) cholesterol following two months of treatment. The atherogenic impact additionally declined essentially in the above gathering demonstrating Spirulina to be upand-comer liable for this impact (18). ...
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Exposure to arsenic is common, but unconscious, inducing major imbalances especially in the digestive tract, lungs, skin. Contamination is achieved by exposure to arsenic in the air, soil, groundwater, food. It is noted the use of arsenic in pesticides, herbicides, paints, wood preservatives, drinking water, various foods with a wide range of consumption (seafood, rice – including rice milk, rice bran, rice cereals, rice syrup rice, rice crackers). The diagnosis of arsenic poisoning is an important step in establishing the diet and detoxification treatment, focusing on the cause, not the symptoms. We present the case of a 45-year-old patient with symptoms manifested in the digestive tract for 4 years: abdominal bloating, cramps, vomiting, weekly episodes of acute diarrhea. During these period the patient received multiple treatments depending on the symptoms, without a significant improvement, without performing specific investigations of arsenic poisoning. The personalized diet and treatment plan, used in the case of this patient, for a period of 4 months was distinguished by a total solution of the manifestations presented in the anamnesis stage.
Chapter
Microalgae usually called “Spirulina” in the literature and in commercial packages have been studied as potential sources of protein for food and feed supplementation. These microalgae are produced industrially worldwide, being recognized as GRAS (Generally Recognized as Safe) by the Food and Drug Administration (USA) and accepted by the European Union for human consumption. Apart from a high protein content and balanced amino acid composition, its biomass contains compounds with antioxidant, anti-inflammatory, anti-tumor, anti-viral and anti-microbial activities. Some of these compounds have been determined to boost the immune system and prevent diseases such as hyperglycemia, cancer, diabetes, hypertension, cardiovascular and respiratory disorders. It has also been suggested that the supplementation with Spirulina biomass and/or its extracts could help immune systems to fight different viral infections, including those by SARS-CoV2, the etiologic agent of COVID-19. This immunity boosting activity has been related to the presence of some polysaccharides, carotenoids, phycobiliproteins, fatty acids and biopeptides in the biomass. In this context, this chapter will address the boosting effect of the immune system by Spirulina exploring its antiviral activity and respective mechanisms. The applications of the biomass as a supplement and nutraceuticals production will be also address.
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Chronic arsenic toxicity is a severe disease in men and animals which occurs severely in Bangladesh. Arsenic (As) contamination in ground water used in drinking is the major concern because arsenic is present in human and animal food chain. This work was done in quails with a view to observing the efficacy of spirulina (Spirulina platensis) and vitamin E for prevention of arsenic toxicity. 60 quails were used in this study and animals were divided into control group (T0), arsenic treated group (T1), arsenic plus spirulina treated group (T2) and arsenic plus vitamin E treated group (T3). Each group consists of 15 quails. Quails of T0 group were given normal feed and water and kept as control. Quails of T1, T2 and T3 were given 100 mg arsenic trioxide/L drinking water daily for 30 days. In addition to arsenic trioxide quails of group T2 and T3 were simultaneously fed with spirulina @ 1 gm/kg feed and vitamin E @ 400 mg /kg body weight up to 30 days respectively. Five quails from each group (T0, T1, T2 and T3) were sacrificed at 15 days interval in order to determine haematological parameters. Result showed that in group T1, body weight gain was minimum, whereas in group T2 and T3 the body weight gain in quails were better. Reduction of TEC and Hb values were observed in arsenic treated group T1. Whereas in rest groups the TEC and Hb values were comparatively higher than arsenic treated group. Noticeable change observed in liver and kindey of arsenic treated group in compare to the control group. Histopathological changes also observed in liver and kindey of arsenic treated group in compare to the control group. In conclusion, spirulina and vitamin E have significant effect on body weight, hematological and postmortem and histopathological changes. Asian J. Med. Biol. Res. March 2020, 6(1): 93-98
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This study was conducted on the patients having chronic arsenicosis with a view to evaluate the effectiveness of management by vitamin A,E,C regimen. Prognosis of the patient was evaluated clinically in terms of change in severity of melanosis and keratosis. The patients perception of improvement was also evaluated. Of the 43 patients, 51.2 % used Arsenic Safe Water (up to 0.01mg/L) and took vitamins regularly, 20.9% took vitamin but used arsenic contaminated water, while the rest (27.90%) used the contaminated water and took the regimen irregularly. Improvement of melanosis and keratosis were observed in 90.9% and 86.4% of the patients respectively from amongst those who had used arsenic safe water and had taken regimen the regularly. Indexing Words : Arsenic, Arsenicosis, melanosis, kelatosis, Vitamin A,E & C.
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A prospective non randomized study was carried out to investigate the effect of spirulina -a blue green micro-algae on the conditions of chronic arsenicosis. The study was conducted at the department of Dermatology & Venereology and Pharmacology Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka, Bangladesh. The study was carried out in a total number of 116 patients who were diagnosed as chronic arsenicosis by history and clinical findings by the Department of Dermatology and Venereology, BSMMU, and by analysing urine for the presence of arsenic by the Department of Pharmacology, BSMMU. Out of 116 patients 64 were male and 52 were female, age ranging from 12 years to 60 years. 89% male and 92.3% female patients were malnourished and 64.5%patients were coming from poor socio-economic class. 35,34% were from middle class, none was found from upper class. Out of 116 patients, raindrop pigmentation was found in 100% cases, hyperkeratosis was in 79.3% cases, weakness was in 93% cases, anorexia was in 79.3% cases, dyspnoea was in 26.7% cases and conjunctivitis was in 25% cases. Anaemia, oedema, jaundice was found in 82.75%, 6.9% and 2.5% cases respectively. Administration of spirulina in a dosage of l O gm/day per os for 4 months resulted in the improvement of signs and symptoms of arsenicosis including the pigmantary and hyperkeratotic lesions and physical weakness. However it can not be over emphasized about this beneficial effect of spirulina in arsenicosis unless a study is carried out amongst large sample with case control over a longer duration.
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1.1 Properties and analytical procedures: Arsenic is a metalloid widely distributed in the earth's crust and present at an average concentration of 2 mg/kg. It occurs in trace quantities in all rock, soil, water and air. Arsenic can exist in four valency states: -3, 0, +3 and +5. Under reducing conditions, arsenite (As(III)) is the dominant form; arsenate (As(V)) is generally the stable form in oxygenated environments. Elemental arsenic is not soluble in water. Arsenic salts exhibit a wide range of solubilities depending on pH and the ionic environment. There is a variety of instrumental techniques for the determination of arsenic. These include AAS, AFS, ICP-AES, ICP-MS and voltammetry. Some of these (e.g. ICP-MS) can serve as element-specific detectors when coupled to chromatographic separation techniques (e.g. HPLC and GC). These so-called "hyphenated" methods are used for determining individual arsenic species. Additional sensitivity for a limited range of arsenic compounds can often be achieved by the use of hydride generation techniques. A test kit based on the colour reaction of arsine with mercuric bromide is currently used for groundwater testing in Bangladesh and has a detection limit of 50-100 gg/litre under field conditions. 1.2 Sources and occurrence of arsenic in the environment: Arsenic is present in more than 200 mineral species, the most common of which is arsenopyrite. It has been estimated that about one-third of the atmospheric flux of arsenic is of natural origin. Volcanic action is the most important natural source of arsenic, followed by low-temperature volatilization. Inorganic arsenic of geological origin is found in groundwater used as drinking-water in several parts of the world, for example Bangladesh. Organic arsenic compounds such as arsenobetaine, arseno-choline, tetramethylarsonium salts, arsenosugars and arsenic-containing lipids are mainly found in marine organisms although some of these compounds have also been found in terrestrial species. Elemental arsenic is produced by reduction of arsenic trioxide (As2O3) with charcoal. AS2O3 is produced as a by-product of metal smelting operations. It has been estimated that 70% of the world arsenic production is used in timber treatment as copper chrome arsenate (CCA), 22% in agricultural chemicals, and the remainder in glass, pharmaceuticals and non-ferrous alloys. Mining, smelting of non-ferrous metals and burning of fossil fuels are the major industrial processes that contribute to anthropogenic arsenic contamination of air, water and soil. Historically, use of arsenic-containing pesticides has left large tracts of agricultural land contaminated. The use of arsenic in the preservation of timber has also led to contamination of the environment. 1.3 Environmental transport and distribution: Arsenic is emitted into the atmosphere by high-temperature processes such as coal-fired power generation plants, burning vegetation and volcanism. Natural low-temperature biomethylation and reduction to arsines also releases arsenic into the atmosphere. Arsenic is released into the atmosphere primarily as As2O3 and exists mainly adsorbed on particulate matter. These particles are dispersed by the wind and are returned to the earth by wet or dry deposition. Arsines released from microbial sources in soils or sediments undergo oxidation in the air, reconverting the arsenic to non-volatile forms, which settle back to the ground. Dissolved forms of arsenic in the water column include arsenate, arsenite, methylarsonic acid (MMA) and dimethylarsinic acid (DMA). In well-oxygenated water and sediments, nearly all arsenic is present in the thermodynamically more stable pentavalent state (arsenate). Some arsenite and arsenate species can interchange oxidation state depending on redox potential (Eh), pH and biological processes. Some arsenic species have an affinity for clay mineral surfaces and organic matter and this can affect their environmental behaviour. There is potential for arsenic release when there is fluctuation in Eh, pH, soluble arsenic concentration and sediment organic content. Weathered rock and soil may be transported by wind or water erosion. Many arsenic compounds tend to adsorb to soils, and leaching usually results in transportation over only short distances in soil. Three major modes of arsenic biotransformation have been found to occur in the environment: redox transformation between arsenite and arsenate, the reduction and methylation of arsenic, and the biosynthesis of organoarsenic compounds. There is biogeochemical cycling of compounds formed from these processes. 1.4 Environmental levels and human exposure: Mean total arsenic concentrations in air from remote and rural areas range from 0.02 to 4 ng/m3. Mean total arsenic concentrations in urban areas range from 3 to about 200 ng/m3; much higher concentrations (> 1000 ng/m3) have been measured in the vicinity of industrial sources, although in some areas this is decreasing because of pollution abatement measures. Concentrations of arsenic in open ocean seawater are typically 2 μg/litre. Arsenic is widely distributed in surface freshwaters, and concentrations in rivers and lakes are generally below 10 μg/litre, although individual samples may range up to 5 mg/litre near anthropogenic sources. Arsenic levels in groundwater average about 1-2 μg/litre except in areas with volcanic rock and sulfide mineral deposits where arsenic levels can range up to 3 mg/litre. Mean sediment arsenic concentrations range from 5 to 3000 mg/kg, with the higher levels occurring in areas of contamination. Background concentrations in soil range from 1 to 40 mg/kg, with mean values often around 5 mg/kg. Naturally elevated levels of arsenic in soils may be associated with geological substrata such as sulfide ores. Anthropogenically contaminated soils can have concentrations of arsenic up to several grams per 100 ml. Marine organisms normally contain arsenic residues ranging from < 1 to more than 100 mg/kg, predominantly as organic arsenic species such as arsenosugars (macroalgae) and arsenobetaine (invertebrates and fish). Bioaccumulation of organic arsenic compounds, after their biogenesis from inorganic forms, occurs in aquatic organisms. Bioconcentration factors (BCFs) in freshwater invertebrates and fish for arsenic compounds are lower than for marine organisms. Biomagnification in aquatic food chains has not been observed. Background arsenic concentrations in freshwater and terrestrial biota are usually less than 1 mg/kg (fresh weight). Terrestrial plants may accumulate arsenic by root uptake from the soil or by adsorption of airborne arsenic deposited on the leaves. Arsenic levels are higher in biota collected near anthropogenic sources or in areas with geothermal activity. Some species accumulate substantial levels, with mean concentrations of up to 3000 mg/kg at arsenical mine sites. Non-occupational human exposure to arsenic in the environment is primarily through the ingestion of food and water. Of these, food is generally the principal contributor to the daily intake of total arsenic. In some areas arsenic in drinking-water is a significant source of exposure to inorganic arsenic. In these cases, arsenic in drinking-water often constitutes the principal contributor to the daily arsenic intake. Contaminated soils such as mine tailings are also a potential source of arsenic exposure. The daily intake of total arsenic from food and beverages is generally between 20 and 300 gg/day. Limited data indicate that approximately 25% of the arsenic present in food is inorganic, but this depends highly on the type of food ingested. Inorganic arsenic levels in fish and shellfish are low (< 1%). Foodstuffs such as meat, poultry, dairy products and cereals have higher levels of inorganic arsenic. Pulmonary exposure may contribute up to approximately 10 μg/day in a smoker and about 1 μg/day in a non-smoker, and more in polluted areas. The concentration of metabolites of inorganic arsenic in urine (inorganic arsenic, MMA and DMA) reflects the absorbed dose of inorganic arsenic on an individual level. Generally, it ranges from 5 to 20 μg As/litre, but may even exceed 1000 μg/litre. In workplaces with up-to-date occupational hygiene practices, exposure generally does not exceed 10 μg/m3 (8-h time-weighted average [TWA]). However, in some places workroom atmospheric arsenic concentrations as high as several milligrams per cubic metre have been reported. 1.5 Kinetics and metabolism: Absorption of arsenic in inhaled airborne particles is highly dependent on the solubility and the size of particles. Both pentavalent and trivalent soluble arsenic compounds are rapidly and extensively absorbed from the gastrointestinal tract. In many species arsenic metabolism is characterized by two main types of reactions: (1) reduction reactions of pentavalent to trivalent arsenic, and (2) oxidative methylation reactions in which trivalent forms of arsenic are sequentially methylated to form mono-, di- and trimethylated products using S-adenosyl methionine (SAM) as the methyl donor and glutathione (GSH) as an essential co-factor.
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Zinc-Induced Arsenite Tolerance in Mice, Kreppel, H., M Liu, J., Liu, Y., Reiciil, F. X., And Klaassen, C. D. (1994). Fundam. Appl. Toxicol. 23, 32-37.
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The microalgae Chlorella spp., Dunaliella spp., and Scenedesmus spp., and the cyanobacteria Spirulina spp., and Aphanizomenon flos-aquae, are being used as nutrient-dense foods and sources of fine chemicals. They have significant amounts of lipid, protein, chlorophyll, carotenoids, vitamins, minerals, and unique pigments. They may also have potent probiotic compounds that enhance health. Their historical and current use are reviewed in this article.
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Alkane arsenate herbicides are available commercially, and their acute toxicity has been well documented in previous studies. Animal studies have indicated that dimercaptosuccinic acid (DMSA) can be used as an oral chelating agent. A 20-y-old white male cocaine addict attempted suicide by drinking approximately 500 ml of a 16% monosodium methanearsenate solution. He vomited 10 or more times and was admitted to the intensive care unit with impending shock and early liver and renal involvement. Four 5-day courses of 30 mg DMSA/kg/24 h were given. This brought the serum arsenic level from 2,871 micrograms/L to 6 micrograms/L, and his urine arsenic level from 78,920 micrograms/L to 21 micrograms/L in 30 d. Renal function tests returned to normal, with normal renal creatinine clearance, normal blood urea nitrogen and serum creatinine. However liver functions were abnormal, with elevation of serum transaminases, which later proved secondary to chronic hepatitis. No side effects of DMSA was encountered during the therapy. DMSA was successfully used to detoxify acute organoarsenate poisoning in a clinical setting, supporting experimental reports in the literature.