Jorge Ruelas-Inzunza

• PhD
• Professor at Instituto Tecnológico de Mazatlán

Mercury (Hg) is a highly toxic heavy metal that presents a notable and worldwide threat to human health and the environment. The most direct method to evaluate the potential effects on human health due to Hg exposure is to monitor biological samples. When biological samples are limited, predictive models are valuable tools to estimate levels of Hg...

The blue shark (Prionace glauca) is the most commonly caught species of Elasmobranchii at the entrance to the Gulf of California. Although fins are the primary target commodity, the entire organism is consumed. This study examined the concentration of Hg and Se in muscle and liver to understand the antagonistic process that occurs between these two...

Mercury (Hg) is mainly incorporated into humans through the consumption of contaminated foods. Mercury was measured and the methyl-Hg (MeHg) concentration was estimated in canned mollusks sold in northwestern Mexico to assess the health risk to consumers. Five mollusk types were considered: oysters, clams, octopuses, mussels, and squids. The Hg con...

This study analyzed total mercury (THg), and selenium (Se) in edible tissues of white shrimp (Litopenaeus vannamei), blue shrimp (L. stylirostris) and brown shrimp (F. californiensis), from three states of the Northwest of Mexico in September and October 2017. Concentrations of THg and Se in the muscle were between 0.026 and 0.829 and 0.126–1.741 µ...

Globally, there is concern about the concentrations of some metals and metalloids in sharks and the associated impacts to themselves and to human consumers. Concentrations of Hg, Cd, and Se reported in muscle, liver and fins of sharks from all the world were reviewed to define geographical patterns of elemental distribution, to model the baseline c...

In this study, the concentrations of Cd and Hg were measured in muscle of juvenile individuals at an importan fishing ground in southeastern Gulf of California to assess the health risk to human consumers considering elemental levels and rate of shark consumption in NW Mexico. Twenty-eight individuals were sampled in September 2019. Quantification...

Human consumption of the thornback guitarfish (Platyrhinoidis triseriata) is concentrated in coastal populations of the Pacific coast of Mexico as its meat is prized for its high quality. This study analyzes the distribution of mercury and selenium in the muscle and liver of Platyrhinoidis triseriata and the risk to human health associated with its...

To balance the risks and benefits of fish consumption, selenium, fatty acids (DHA + EPA), and mercury in fishery products were determined. Analyzed products were canned tuna, frozen tuna (Thunnus albacares), smoked striped marlin (Tetrapturus audax), fresh Pacific sierra (Scomberomorus sierra), fresh dolphinfish (Coryphaena hippurus), fresh tilapia...

Mercury (Hg) and arsenic (As) contamination of fish can be toxic and limit safe human consumption, whereas selenium (Se) can potentially protect fish and consumers from the adverse effects of Hg and As. We assembled datasets of the above-mentioned elements in Canadian freshwater fish and compare them with risk assessment thresholds. We further asse...

The concentrations of As, Cd, Cu, Pb and Zn were measured in muscle tissue of Coryphaena hippurus captured in the southern Gulf of California to determine inter-annual variations and their relation with environmental parameters for the period 2006–2015; additionally, health risk to consumers was assessed according to levels of studied elements and...

Mercury and selenium concentrations and Se:Hg molar ratio in edible muscle and hepatopancreas of the crab Callinectes arcuatus from coastal lagoons of northwest Mexico were determined using atomic absorption spectrophotometry. The three coastal lagoons were Santa María La Reforma (SMLR), Urías (UR), and Huizache-Caimanero (HC); samplings were carri...

Mercury (Hg) was measured in the muscle, liver, and gonads of Haemulopsis elongatus and Pomadasys macracanthus from Mazatlán (SE Gulf of California) to determine the relationships of the hepatosomatic index (HSI) and gonadosomatic index (GSI) of fish with Hg concentrations in the corresponding tissues. Health risk to consumers was assessed by using...

Mercury and selenium were assessed in Mustelus henlei, which is a carnivorous predatory shark that is important for the coastal communities of the northern Mexican Pacific (NMP). Sixty-two individuals were sampled; muscle and liver were isolated and analyzed by atomic absorption spectrophotometry. The mean Hg concentrations (wet weight) obtained fo...

With the aim of determining the benefit from consumption of dolphinfish Coryphaena hippurus from La Paz and Cabo San Lucas in the southern area of the Gulf of California, mercury (Hg) and selenium (Se) were measured in liver and muscle of specimens (n = 362) collected between 2006 and 2013. Mean levels of Hg in muscle (0.61 μg g⁻¹) and liver (0.42...

The present study shows the human health risk of Cd, Cu, Hg and Zn by consumption of clams Megapitaria squalida from Northwest Mexico, collected in 2013. The mean concentration for each metal in the soft tissue was: Zn > Cu > Cd > Hg; and mean values of 68.89 ± 37.59—30.36 ± 27.19, 8.77 ± 1.35—6.80 ± 0.36, 4.47 ± 0.21—3.18 ± 0.63 and 0.99 ± 0.81—0....

With the aim of assessing health risk to shark consumers, cadmium, mercury, and selenium were measured in muscle of Sphyrna lewini from four coastal states (Baja California Sur, Sinaloa, Nayarit, and Colima) in western Mexico. According to length of specimens, three age modes were found: juveniles and neonates (the majority of the individuals), pre...

El golfo de California, al igual que otros grandes ecosistemas marinos del mundo, ha experimentado diversos impactos ambientales asociados con las actividades humanas (sobrepesca, pérdida de biodiversidad y hábitats, cambio climático, y contaminación). El año 2017 publicamos una revisión sobre el estatus ambiental de este valioso ecosistema (Páez-O...

Adult sharpnose sharks (Rhizoprionodon longurio) with a mean total length of 110.93 ± 5.30 cm were obtained from a local fishery in Mazatlán (Southeast Gulf of California, Mexico). The total mercury content in muscle was analyzed by cold vapor atomic absorption spectrophotometry. The minimum and maximum total mercury content were 0.77 ± 0.23 and 2....

Oysters of Urías lagoon (NW Mexico) were collected every second month from November 2012 to September 2013, to determine the variations of their mercury (Hg²⁺) content and assess their suitability for human consumption. Concentrations were significantly higher in November than in March and May, which indicates that variability does not depend on th...

With the aim of knowing the distribution of As, Hg, and Se in skipjack (Katsuwonus pelamis, Linnaeus, 1758) and yellowfin tuna (Thunnus albacares, Bonnaterre, 1788) from the Eastern Pacific, elemental concentrations were determined in the muscle and liver; As species were also analyzed in the stomach content. Additionally, health risk for consumers...

We evaluated the total Hg concentration in different tissues of squalid callista Megapitaria squalida in order to measure Hg distribution in tissue and to estimate human health risk. Samples were obtained by free diving in the SW Gulf of California, Mexico. Concentrations are given on a wet weight basis. A total of 89 squalid callista specimens wer...

We assessed human health risk due to mercury (Hg) concentrations in fish from three coastal lagoons (Urías, Huizache, and Teacapán) in the SE Gulf of California. We also determined Hg distribution in muscle and liver of analyzed ichthyofauna and compared the results among studied areas according to tissue, season, and lagoon system by using multiva...

Total mercury (Hg) concentrations were determined by atomic absorption spectrophotometry in muscles and liver of composite samples of Mugil cephalus and M. curema collected during November 2013 and in January, April, and July 2014 from the coastal lagoons Altata-Ensenada del Pabellón (AEP), Ceuta (CEU), and Teacapán-Agua Brava (TAG) of Sinaloa Stat...

We aimed at characterizing the methylmercury (MeHg) exposure through fish consumption in two populations (common general and fishing related population) using a probabilistic health risk assessment in children, women of childbearing age and adults in Mazatlán. The hazard quotients (HQ) were obtained from fish consumption, defined through a survey,...

We determined the levels of Cd and Pb in liver and muscle of demersal fish from three lagoon systems (Ur?as, Huizache, and Teacap?n) in the SE Gulf of California with the purpose of comparing the studied metals in fish from the three ecosystems and to assess the potential human health risk. Considering the number of individuals, the sequence of fis...

In order to ascertain if Cu, Fe, and Zn are differentially accumulated in fish tissues, metal concentrations were measured in the muscle and liver of bycatch fish from the states of Sinaloa (189 specimens, 7 species) and Guerrero (152 individuals, 8 species) in the Mexican Pacific Coast during March and November 2011. Additionally, metal levels wer...

With the aim of knowing annual variations of Hg concentrations in muscle and liver of blue marlin (Makaira nigricans) from the southern Gulf of California, fish were collected between 2005 and 2012 in three areas. In general, Hg levels were more elevated in liver than in muscle. Variations of Hg concentrations in muscle and liver among the studied...

The White and Striped mullets (Mugil curema and M. cephalus) are highly abundant and commercially important estuarine fish in northwest (NW) Mexico. Because of their feeding habits and habitat, they are likely to accumulate mercury (Hg) in their muscle and liver. The objectives of this study were to determine total Hg distribution in the tissues of...

Cadmium, lead, copper, and zinc were analyzed in the dorsal muscle, liver, gonad, and stomach contents of 67 sailfish, Istiophorus platypterus, from the Eastern Pacific. Muscle exhibited the following pattern (μg/g wet weight): Zn (15.05 ± 1.24) > Cu (0.461 ± 0.026) > Cd (0.434 ± 0.099) > Pb (0.025 ± 0.001); liver Zn (119.1 ± 7.6) > Cd (95.1 ± 11.0...

We determined total Hg and Se contents of hepatopancreas, exoskeleton, and muscle, and the Se:Hg molar ratios in the muscle of shrimps Farfantepenaeus californiensis and Litopenaeus stylirostris caught in NE Pacific Mexican waters. Total Hg mean values in muscle, hepatopancreas, and exoskeleton were 0.31 ± 0.26, 0.28 ± 0.29, and 0.24 ± 0.06 μg g−1,...

The mercury content of mullets and black mojarras of Urías lagoon (NW Mexico) were determined every second month from November 2012 to September 2013, to determine differences related to season or to trophic levels. The Hg contents of the muscle were significantly higher in mojarras, confirming that Hg contents tend to increase along the food chain...

Concentrations of mercury (Hg) were quantified in muscle tissues of the Pacific angel shark, Squatina californica sampled from Southern Gulf of California, Mexico, considering total length, sex, diet and the dietary risk assessment. High Hg levels are typically associated with carnivorous fishes, however S. californica showed low Hg concentrations...

With the aim of determining arsenic (As) and selenium (Se) concentrations in bycatch fishes from SW Mexico and comparing elemental concentrations with limits for human consumption set in the national and international legislation, three fish species (Diapterus peruvianus, Pseudupeneus grandisquamis, and Trachinotus kennedyi) were collected from Gue...

We determined the Hg content of blood, placenta and umbilical cord of 20 pregnant females of the viviparous Pacific sharpnose shark, Rhizoprionodon longurio and of the livers of the embryos contained in their right and left uterus, aiming to provide information on the amount of this metal offloaded during pregnancy by the mother to the embryos. Hg...

Uptake of mercury (Hg) through fish consumption is one of the key aspects of the Hg cycle in the aquatic ecosystems. In tropical latitudes, biomonitoring of Hg in freshwater reservoirs is scarce. The objectives of the study were to determine Hg distribution in muscle, liver, and kidney of blue tilapia Oreochromis aureus from a dam located in a mini...

The total mercury (Hg) content of the soft tissues of cultured oysters of the genus Crassostrea obtained during the dry and rainy seasons at sampling sites of NW Mexico with different degrees of urbanization, was determined by cold vapor atomic absorption spectrophotometry. Hg levels ranged from 0.05 to 0.37 µg/g (dry weight) and no significant dif...

The Estero de Urias Lagoon (EUL) is an inner shelf barrier coastal lagoon, located in the Mexican Pacific Coast (SE Gulf of California). It is surrounded by Mazatlan City, one of the most important international tourist areas of Mexico. To provide a comprehensive reassessment of the concentration levels and spatial variability of Hg and Pb-210 in t...

Mercury (Hg) is the most dangerous trace element present in the edible parts of fishes and invertebrates. With the aim of having a general view on Hg occurrence in commercially exploited biota (fish and invertebrates) from selected estuarine systems of Mexico, we compiled information related to Hg levels in fish (elasmobranchs and teleosts), shrimp...

With the aim of determining Hg distribution in muscle and liver of bycatch fish from Guerrero state in the Eastern Pacific Ocean and assess the potential risk to consumer, Hg was quantified in 14 species of bycatch fish. For the majority of fish the order of Hg levels was liver > muscle. The highest concentration corresponded to the liver of Isopis...

With the aim of knowing Hg distribution in selected tissues of myliobatid stingrays and assessing health risk to Mexican population, Hg concentration was determined in the muscle and liver of four ray species. Total Hg levels were determined by cold vapor atomic absorption spectrophotometry. With respect to the muscle, devil rays (Mobula spp.) show...

We determined total mercury (Hg) distribution in muscle and liver of ten ray species and assessed health risk considering Hg levels in muscle and average consumption of rays in Mexico. Rays were collected from five sites in NW Mexico between March and November 2012. Hg concentrations ranged from 4.465μgg(-1) in muscle of the longtail stingray Dasya...

Though mercury (Hg) occurs naturally in the environment, anthropogenic activities have affected its global cycle in ways that mobilize increasing amounts of this metal; currently, such human-related activities mobilize more Hg than do natural processes (Fitzgerald and Lamborg 2005). It has been estimated that the quantity of Hg mobilized into the a...

Se recolectaron 26 muestras de particulado atmosférico en tres sitios durante un año y 12 muestras de suelo superficial. Las muestras atmosféricas fueron recolectadas por bombeo en filtros de nitrocelulosa (0.45 μm de poro). Las muestras de suelo se obtuvieron manualmente con utensilios de plástico. Las concentraciones de Hg se obtuvieron por espec...

Hg was analyzed in seven tissues of 52 common shoveler Anas clypeata collected from the coast of SE Gulf of California. Mean Hg concentrations were highest in the liver (2,885 ng g(-1)) and lowest in the gizzard (621 ng g(-1)); they followed the order: liver, feathers > muscle tissue and tissues of the circulatory system > digestive organs. Hg leve...

Baseline Hg concentration in bycatch fish from the SE Gulf of California were determined in muscle and liver of 19 species. Levels of Hg in muscle were compared with legal limits of this element in national and international legislation. Considering all fish species, mean concentrations in liver (2.458±1.997μgg(-1)) were significantly higher (p<0.0...

Daily mineral intake (DMI) of Cu and Zn, percentage weekly intake (PWI) of As, Cd, Hg, Pb, and doses of (210)Po were estimated by using their elemental concentration in muscle of two tuna species and the average tuna consumption in Mexico. Skipjack tuna Katsuwonus pelamis had significantly (p < 0.05) higher levels of As (1.38 μg g(-1) dw) and Cu (1...

En México el pescado se vende fresco-enhielado en diferentes sitios de venta, pero no se cuenta con un control permanente de la calidad sanitaria por parte de las autoridades. El objetivo de este trabajo fue evaluar el contenido de histamina y la calidad microbiológica de las especies sierra del Pacífico, lisa y dorado, comercializados en el puerto...

This investigation sought to assess the biological responses to Pb along a simplified four-level food chain, from the primary producer, the microalgae Tetraselmis suecica, grown in a control medium with < 1 µg/L of Pb and exposed to a sublethal dose (20 µg/L of Pb) and used as the base of a simulated food chain, through the primary-, secondary-, an...

With the purpose of knowing seasonal variations of Cd, Cr, Hg and Pb in a river basin with past and present mining activities, elemental concentrations were measured in six fish species and four crustacean species in Baluarte River, from some of the mining sites to the mouth of the river in the Pacific Ocean between May 2005 and March 2006. In fish...

Total mercury and organic mercury were measured in ten fish species from the Mexican Pacific ocean to have a general view on the ratio of total mercury-organic mercury and potential implications on human health. Highest concentration of total mercury was recorded in muscle tissue of Carcharhinus leucas (0.62 μg g⁻¹ wet weight). Organic mercury was...

Mercury concentrations were assessed in the sea turtle Lepidochelys olivacea from a nesting colony of Oaxaca, Mexico; 25 female turtles were sampled, a total of 250 eggs were collected during the season 2005-2006. Higher concentrations were found in yolk fraction, while in blood and albumen mean levels were below of 0.0010μg g(-1) dry wt. On the ba...

A hazard quotient (HQ) was evaluated for Mexican population considering Hg levels and consumption rates. Fish and shrimp were caught in selected coastal areas. HQ's ranged from 0.004 to 0.01 in shrimp; from 0.004 to 1.04 in fish from NW Mexico; and from 0.02 to 0.19 in fish from the Gulf of Mexico. Highest HQ in fish were found in carnivorous fish...

Trace metals (Cd, Cu, Ni, and Zn) concentrations were assessed in the sea turtle Lepidochelys olivacea from a nesting colony of Oaxaca, Mexico. Twenty-five female turtles were sampled, a total of 250 eggs were collected during the "arribada" event of the 2005-2006 season. Zn concentrations were highest in the yolk [72.3 ± 10.9 μg/g dry weight (dw)]...

The objective of this investigation was to assess the transfer of lead (Pb) along an experimental, four-level food chain: Tetraselmis suecica (phytoplankton) → Artemia franciscana (crustacean, brine shrimp) → Litopenaeus vannamei (crustacean, white shrimp) → Haemulon scudderi (fish, grunt). T. suecica was exposed to a sublethal dose of Pb in soluti...

With the aim of knowing levels of Cu, Fe, and Zn in the edible portion of tunas Thunnus albacares and Katsuwonus pelamis, these elements were measured in 73 fish collected in the eastern Pacific. Additionally, trophic transfer (TF) and dietary mineral intake (DMI) of analyzed metals were determined. The most elevated average concentration of Zn (31...

The purpose of this study was to produce silage and determine changes in the chemical and microbiological wastes smoked yellowfin tuna (Thunnus albacares) and tilapia filleting residue (Oreochromis sp), fermented with a commercial inoculum strain Lactobacillus casei Shirota. Procedures were used rustic and easy access to materials to be used as fis...

The purpose of this study was to produce silage and determine changes in the chemical and microbiological wastes smoked yellowfin tuna (Thunnus albacares) and tilapia filleting residue (Oreochromis sp), fermented with a commercial inoculum strain Lactobacillus casei Shirota. Procedures were used rustic and easy access to materials to be used as fis...

With the objective of estimating the temporal variation and bioavailability of Cd, Cu, Pb and Zn in Coatzacoalcos estuary, the biota-sediment accumulation factors (BSAF) were calculated. For this purpose, surficial sediments and clams from 14 selected sites were collected during three climatic seasons. In surficial sediments, highest levels of Cd a...

Concentrations of lead were assessed in the sea turtle, Lepidochelys olivacea, from a nesting colony of the Eastern Pacific. Twenty-five female turtles were sampled and a total of 250 eggs were collected during the "arribada" event of the 2005-2006 season. Considering the nesting season, the maternal transfer of lead (Pb) via egg-laying, in terms o...

We measured organic and total Hg in muscle tissue of five species of aquatic birds from the south-eastern gulf of California region, Mexico. Concentrations of total and organic Hg measured in Pelecanus occidentalis were the highest (2.85 and 2.68 microgg(-1)); lowest values of organic Hg (0.20 microgg(-1)) and total Hg (0.47 microgg(-1)) were detec...

Variation of mercury (Hg) in sediments and biota from Coatzacoalcos estuary during the dry, rainy and windy seasons was estimated. In sediments, Hg concentrations ranged from 0.07μg g−1 in site 13 (Ixhuatepec) located upstream, to 1.06μg g−1 in site 3 (Coatzacoalcos river), located in the industrialized area. Highest enrichment factor (EF) and inde...

With the aim of giving an overview on concentration and distribution of Cd, Cu, and Pb in fish from the coasts of Sinaloa state (SE Gulf of California), specimens with different feeding habits were collected in five locations. Sampling occurred between June 2003 and March 2004. Metal analyses on fish tissues were made by graphite furnace (Cd, Pb) a...

The aim of the work was to obtain a comparative view of the trophic distribution of Cd, Pb, and Zn in different organisms of the food web (from primary producers to top predators), considering representative species in Altata-Ensenada del Pabellón subtropical lagoon (SE Gulf of California). The study provides the first quantitative information on t...

Within the framework of the North America Free Trade Agreement (NAFTA) among Canada, the United States and Mexico, a relevant issue related to the environment and human health is the reduction of mercury (Hg) emissions. Such emissions are being released from diverse anthropogenic actions including industrial and commercial processes, and urban and...

With the aim of knowing seasonal variability of lead in fish and bivalve species from Coatzacoalcos estuary, biota collected during three seasons was examined. In muscle tissue of fish, the highest level (5.4 microg g(-1)) was found in the longnose gar Lepisosteus osseus from San Francisco stream (a highly impacted site); the lowest value (0.2 micr...

With the aim of knowing concentrations of Cd, Cu, Fe, Mn, Pb and Zn; percentage of daily mineral intake (PMI) for essential elements and percentage of weekly intake (PWI) of toxic metals in commercial fish from 2 coastal lagoons in the Eastern Gulf of California, analyses were carried out in 9 species. Highest values of Cd were detected in the live...

No abstract available.

In order to know the concentration of mercury in surface sediments, macroalgae and clams from Guaymas Bay, Mexico, 20 surface sediment samples and several individuals of Codium amplivesciculatum (3), Enteromorpha clathrata (4), Gracilaria subsecundata (2), Ulva lactuca (2), Chione subrugosa (80) and Crassostrea gigas (40) were collected and their H...

Twenty two specimens of vestimentiferan tube worms Riftia pachyptila were collected from Guaymas Basin. The distribution of ten trace metals in trophosome and vestimentum was investigated. Highest mean concentrations of Co, Cu and Fe were detected in the trophosome; while higher mean levels of Cd, Hg, Mn, Ni, Pb and Zn were measured in the vestimen...

The Altata-Ensenada del Pabellon lagoon system is located in the central part of Sinaloa state, NW Mexico. The major sources of pollution are represented by the waste effluents from the intensive agriculture and the urban sewage from the cities of Culiacán (population of 750000) and Navolato (population of 50000). In this lagoon system diverse pena...

With the aim of knowing Cd, Cu, Fe, Mn, Pb, and Zn concentrations in selected tissues of birds from two places at Altata-Ensenada del Pabellón lagoon in the SE Gulf of California, 39 specimens of 14 species were analyzed. Migratory birds in this study showed the highest values of Cd, Cu, and Pb in liver; Fe and Mn, in viscera; and Zn, in feathers....

This work provides data on the concentration and distribution of Cd, Cu, Fe, Hg, Mn, Pb and Zn in different tissues of the vent clam Vesicomya gigas. Twelve clams were collected from the Guaymas basin (Gulf of California) during the Extreme 2000 expedition (January 14–19, 2000) onboard the deep-sea research vehicle Alvin. Analysis of Hg was made by...

Four gray whales Eschrichtius robustus and eleven spinner dolphins Stenella longirostris were found stranded along the coasts of the lower Gulf of California, Mexico. Muscle, kidney and liver samples from all the specimens were used for mercury (Hg) analysis. Mean concentrations of total Hg (THg) were significantly different (P<0.05) in all the tis...

Four gray whales Eschrichtius robustus and eleven spinner dolphins Stenella longirostris were found stranded along the coasts of the lower Gulf of California, Mexico. Muscle, kidney and liver samples from all the specimens were used for mercury (Hg) analysis. Mean concentrations of total Hg (THg) were significantly different (P < 0.05) in all the t...

With the aim of knowing the concentration and distribution of essential and nonessential metals in selected tissues of whales, analysis of Cd, Cu, Fe, Mn, Pb and Zn were carried out in kidney, liver and muscle of the gray whale Eschrichtius robustus and the sperm whale Physeter catodon. Whales were found stranded in the southeast Gulf of California...

To evaluate the relative bioavailability of Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn in the coastal waters of one selected site in Mazatlán Harbor, different filter feeder organisms, an oyster (Crassostrea corteziensis), a mussel (Mytella strigata) and a barnacle (Fistulobalanus dentivarians), were sampled during 1 year. Seasonal and interspecific variati...

Concentrations of Cd, Cu, Cr, Fe, Mn, Ni, Ag, Pb, and Zn in soft and hard tissues of barnacles from eight sampling sites in six harbours on the subtropical Pacific Coast of Mexico were determined by atomic absorption spectrophotometry. Some inter-regional differences in metal concentrations, especially concerning Zn, Mn, Fe, Cd, and Pb, were identi...