Janneke G F Hogervorst

Maastricht University, Maestricht, Limburg, Netherlands

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Publications (24)108.76 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Nails contain genomic DNA that can be used for genetic analyses, which is attractive for large epidemiologic studies that have collected or are planning to collect nail clippings. Study participants will more readily participate in a study when asked to provide nail samples than when asked to provide a blood sample. In addition, nails are easy and cheap to obtain and store compared with other tissues. We describe our findings on toenail DNA in terms of yield, quality, genotyping a limited set of SNPs with the Sequenom MassARRAY iPLEX platform and high-density genotyping with the Illumina HumanCytoSNP_FFPE-12 DNA array (>262,000 markers). We discuss our findings together with other studies on nail DNA and we compare nails and other frequently used tissue samples as DNA sources. Although nail DNA is considerably degraded, genotyping a limited set of SNPs with the Sequenom MassARRAY iPLEX platform (average sample call rate, 97.1%) and high-density genotyping with the Illumina HumanCytoSNP_FFPE chip (average sample call rate, 93.8%) were successful. Nails are a suitable source of DNA for genotyping in large-scale epidemiologic studies, provided that methods are used that are suitable or optimized for degraded DNA. For genotyping through (next generation) sequencing where DNA degradation is less of an issue, nails may be an even more attractive DNA source, because it surpasses other sources in terms of ease and costs of obtaining and storing the samples. It is worthwhile to consider nails as a source of DNA for genotyping in large-scale epidemiologic studies. See all the articles in this CEBP Focus section, "Biomarkers, Biospecimens, and New Technologies in Molecular Epidemiology." Cancer Epidemiol Biomarkers Prev; 23(12); 2703-12. ©2014 AACR. ©2014 American Association for Cancer Research.
    12/2014; 23(12):2703-12.
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    ABSTRACT: Acrylamide, a probable human carcinogen, is present in heat-treated carbohydrate-rich foods. Epidemiological studies have not shown a clear association between acrylamide intake and colorectal cancer risk. This may be due to the molecular heterogeneity in colorectal tumors, which was not taken into consideration before. Since the acrylamide metabolite glycidamide induces specific DNA mutations in rodents, we investigated whether acrylamide is associated with colorectal cancer risk characterized by mutations in KRAS and APC; key genes in colorectal carcinogenesis. This case-cohort analysis, within the Netherlands Cohort Study on diet and cancer, was based on 7.3 years of follow-up. Acrylamide intake was assessed with a food frequency questionnaire. Mutation analysis of codons 1286-1520 in exon 15 in APC and codons 12 and 13 in exon 1 in KRAS was performed on tumor tissue of 733 cases. Hazard ratios were calculated using Cox proportional hazards analysis. Among men, acrylamide intake was statistically significantly associated with an increased risk of particularly tumors with an activating KRAS mutation (HR 4(th) quartile vs. 1(st): 2.12 (95% CI: 1.16-3.87), p-trend: 0.01). Among women, acrylamide intake was statistically significantly associated with a decreased risk of particularly tumors with a truncating APC mutation (4(th) quartile vs. 1(st): 0.47 (95% CI: 0.23-0.94), p-trend: 0.02), but only in the highest quartile of intake. This is the first study to show that acrylamide might be associated with colorectal cancer with specific somatic mutations, differentially in men and women. More research is needed to corroborate or refute these findings.
    Carcinogenesis 01/2014; · 5.64 Impact Factor
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    ABSTRACT: Background The rodent carcinogen acrylamide was discovered in 2002 in commonly consumed foods. Epidemiological studies have observed positive associations between acrylamide intake and endometrial, ovarian and breast cancer risks, which suggests that acrylamide may have sex-hormonal effects. Methods We cross-sectionally investigated the relationship between acrylamide intake and plasma levels of sex hormones and SHBG among 687 postmenopausal and 1300 premenopausal controls from nested case-control studies within the Nurses' Health Studies. Results There were no associations between acrylamide and sex hormones or SHBG among premenopausal women overall or among never-smokers. Among normal-weight premenopausal women, acrylamide intake was statistically significantly positively associated with luteal total and free estradiol levels. Among postmenopausal women overall and among never-smokers, acrylamide was borderline statistically significantly associated with lower estrone sulfate levels but not with other estrogens, androgens, prolactin or SHBG. Among normal weight women, (borderline) statistically significant inverse associations were noted for estrone, free estradiol, estrone sulfate, DHEA, and prolactin, while statistically significant positive associations for testosterone and androstenedione were observed among overweight women. Conclusions Overall, this study did not show conclusive associations between acrylamide intake and sex hormones that would lend unequivocal biological plausibility to the observed increased risks of endometrial, ovarian and breast cancer. The association between acrylamide and sex hormones may differ by menopausal and overweight status. We recommend other studies investigate the relationship between acrylamide and sex hormones in women, specifically using acrylamide biomarkers. Impact The present study showed some interesting associations between acrylamide intake and sex hormones that urgently need confirmation.
    Cancer Epidemiology Biomarkers &amp Prevention 08/2013; · 4.56 Impact Factor
  • European journal of cancer prevention: the official journal of the European Cancer Prevention Organisation (ECP) 09/2012; · 2.21 Impact Factor
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    ABSTRACT: Acrylamide, a probable human carcinogen, is present in many everyday foods. Since the finding of its presence in foods in 2002, epidemiological studies have found some suggestive associations between dietary acrylamide exposure and the risk of various cancers. The aim of this prospective study is to investigate for the first time the association between dietary acrylamide intake and the risk of several histological subtypes of lymphatic malignancies. The Netherlands Cohort Study on diet and cancer includes 120,852 men and women followed-up since September 1986. The number of person years at risk was estimated by using a random sample of participants from the total cohort that was chosen at baseline (n =5,000). Acrylamide intake was estimated from a food frequency questionnaire combined with acrylamide data for Dutch foods. Hazard ratios (HRs) were calculated for acrylamide intake as a continuous variable as well as in categories (quintiles and tertiles), for men and women separately and for never-smokers, using multivariable-adjusted Cox proportional hazards models. After 16.3 years of follow-up, 1,233 microscopically confirmed cases of lymphatic malignancies were available for multivariable-adjusted analysis. For multiple myeloma and follicular lymphoma, HRs for men were 1.14 (95% CI: 1.01, 1.27) and 1.28 (95% CI: 1.03, 1.61) per 10 µg acrylamide/day increment, respectively. For never-smoking men, the HR for multiple myeloma was 1.98 (95% CI: 1.38, 2.85). No associations were observed for women. We found indications that acrylamide may increase the risk of multiple myeloma and follicular lymphoma in men. This is the first epidemiological study to investigate the association between dietary acrylamide intake and the risk of lymphatic malignancies, and more research into these observed associations is warranted.
    PLoS ONE 01/2012; 7(6):e38016. · 3.53 Impact Factor
  • Clinical & Experimental Allergy 10/2011; 41(10):1493-4. · 4.79 Impact Factor
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    ABSTRACT: Acrylamide, a probable human carcinogen, was detected in various heat-treated foods such as French fries and potato crisps. Recently, positive associations have been found between dietary acrylamide intakes, as estimated with a food frequency questionnaire using an acrylamide database, and cancer risk in some epidemiological studies. As acrylamide levels vary considerably within the same type of foods, a validation study was performed to investigate whether use of an acrylamide food database containing calculated mean acrylamide content, based on extensive sampling and chemical analysis of Dutch foods (several samples per food), can classify subjects with respect to true acrylamide intake. We used the data from a 24-h duplicate diet study. The acrylamide content of 39 Dutch 24-h duplicate diets collected in 2004 was estimated using the mean acrylamide levels of foods available from the database and the menu list, on which the participants of the duplicate diet study had listed the amounts of individual foods and drinks in household units. Next, the acrylamide content of the total duplicate diets was analytically measured and correlated to the estimated acrylamide contents. The Spearman's correlation coefficient between chemically determined acrylamide content and the calculated acrylamide content of the duplicate diets was 0.82 (P<0.001). This study indicates that it is possible to classify subjects with respect to acrylamide intake if mean instead of actual content of each food is applied. The database can therefore be applied in epidemiological studies on acrylamide intake and cancer risk, such as the Netherlands Cohort Study on Diet and Cancer.
    European journal of clinical nutrition 03/2010; 64(5):534-40. · 3.07 Impact Factor
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    ABSTRACT: Since 2002, it is known that the probable human carcinogen acrylamide is present in commonly consumed carbohydrate-rich foods, such as French fries and potato chips. In this review, the authors discuss the body of evidence on acrylamide carcinogenicity from both epidemiological and rodent studies, including variability, strengths and weaknesses, how both types of evidence relate, and possible reasons for discrepancies. In both rats and humans, increased incidences of various cancer types were observed. In rats, increased incidences of mammary gland, thyroid tumors and scrotal mesothelioma were observed in both studies that were performed. In humans, increased risks of ovarian and endometrial cancers, renal cell cancer, estrogen (and progesterone) receptor-positive breast cancer, and oral cavity cancer (the latter in non-smoking women) were observed. Some cancer types were found in both rats and humans, e.g., endometrial cancer (observed in one of the two rat studies), but there are also some inconsistencies. Interestingly, in humans, some indications for inverse associations were observed for lung and bladder cancers in women, and prostate and oro- and hypopharynx cancers in men. These latter observations indicate that genotoxicity may not be the only mechanism by which acrylamide causes cancer. The estimated risks based on the epidemiological studies for the sites for which a positive association was observed were considerably higher than those based on extrapolations from the rat studies. The observed pattern of increased risks in the rat and epidemiological studies and the decreased risks in the epidemiological studies suggests that acrylamide might influence hormonal systems, for which rodents may not be good models.
    Critical Reviews in Toxicology 02/2010; 40(6):485-512. · 6.25 Impact Factor
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    ABSTRACT: Acrylamide, a potential human carcinogen, has been discovered in a variety of heat-treated carbohydrate-rich food products. Previously, dietary acrylamide intake was shown to be associated with endocrine-related cancers in humans. We assessed the association between dietary acrylamide intake and risk of postmenopausal breast cancer stratified by estrogen and progesterone receptor status. This study was embedded within the Netherlands Cohort Study on diet and cancer, which was initiated in 1986 enrolling 62,573 women aged 55-69 years at baseline. After 13.3 years of follow-up, 2225 incident breast cancer cases were ascertained, with hormone receptor status information for 43%. Cox proportional hazards analysis was applied to determine hazard ratios in quintiles of dietary acrylamide intake stratifying on estrogen receptor (ER) and progesterone receptor (PR) and smoking status. No association was observed for overall breast cancer or receptor-negative breast cancer risk, irrespective of smoking status. A statistically non-significantly increased risk of ER positive, PR positive and joint receptor-positive breast cancer was found in never-smoking women. The multivariable-adjusted hazard ratios were 1.31 (95% CI: 0.87-1.97, P (trend) = 0.26) for ER+, 1.47 (0.86-2.51, P (trend) = 0.14) for PR+, and 1.43 (0.83-2.46, P (trend) = 0.16) for ER+PR+, when comparing women in the highest quintile of acrylamide intake (median 36.8 microg/day) to women in the lowest (median 9.5 microg/day). This study showed some indications of a positive association between dietary acrylamide intake and receptor-positive breast cancer risk in postmenopausal never-smoking women. Further studies are needed to confirm or refute our observations.
    Breast Cancer Research and Treatment 12/2009; 122(1):199-210. · 4.47 Impact Factor
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    ABSTRACT: Acrylamide exposure has been related to an increased incidence of oral and thyroid tumors in animal studies. In 1986, 120,852 persons (aged 55-69 years) were included in the Netherlands Cohort Study. Dietary acrylamide intake was assessed with a food frequency questionnaire and was based on chemical analysis of all relevant Dutch foods. Hazard ratios were adjusted for smoking and other confounders. After 16.3 years of follow-up, there were 101, 83, 180, and 66 cases of oral cavity, oro-hypopharynx, larynx, and thyroid cancer, respectively. Average daily dietary acrylamide intake was 21.8 microg (standard deviation, 12.1). Dietary acrylamide intake was not associated with increased risk of oral cavity (hazard ratio (HR) per 10-microg intake/day = 0.90, 95% confidence interval (CI): 0.73, 1.10), oro-hypopharynx (HR = 0.74, 95% CI: 0.53, 1.03), larynx (HR = 1.05, 95% CI: 0.91, 1.21), or thyroid (HR = 1.03, 95% CI: 0.82, 1.27) cancer. For nonsmokers, hazard ratios were not increased either. Dietary acrylamide was statistically significantly associated with increased risk of oral cavity cancer in female nonsmokers, but case numbers were small. Dietary acrylamide intake was not positively associated with risk of head-neck and thyroid cancer, except with oral cavity cancer risk for female nonsmokers. A negative association for males was indicated.
    American journal of epidemiology 09/2009; 170(7):873-84. · 5.59 Impact Factor
  • Janneke Hogervorst, Leo Schouten, Piet van den Brandt
    Food and chemical toxicology: an international journal published for the British Industrial Biological Research Association 09/2009; 47(11):2871-2; author reply 2873-4. · 2.99 Impact Factor
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    ABSTRACT: Acrylamide is a probable human carcinogen, which is present in several heat-treated foods. In epidemiologic studies, positive associations with endometrial, ovarian, and renal cell cancer risk have been observed. The incidence of central nervous system tumors was increased upon acrylamide administration in drinking water to rats. In the current study, the association between dietary acrylamide intake and human brain cancer risk was investigated for the first time. In 1986, 120,852 persons (ages 55-69 years) were included in the Netherlands Cohort Study on diet and cancer. At baseline, a random subcohort of 5,000 participants was randomly selected from the total cohort for a case-cohort approach. Acrylamide intake was assessed with a food frequency questionnaire at baseline and based on acrylamide analyses in relevant Dutch foods. Hazard ratios (HR) were calculated using Cox proportional hazards analysis. Subgroup analyses were done for microscopically verified brain cancer, astrocytic gliomas, high-grade astrocytic gliomas, and never-smokers. The acrylamide risk estimates were adjusted for possible brain cancer risk factors. After 16.3 years of follow-up, 216 brain cancer cases were available for analysis. The multivariable-adjusted HR per 10 microg/d increment of acrylamide intake was 1.02 (95% confidence interval, 0.89-1.16). HRs were not significantly increased either when dietary acrylamide intake was analyzed as a categorical variable. Also, there was no association in the subgroups based on histology and smoking. In this prospective cohort study, acrylamide intake was not associated with brain cancer risk.
    Cancer Epidemiology Biomarkers &amp Prevention 05/2009; 18(5):1663-6. · 4.56 Impact Factor
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    ABSTRACT: Acrylamide is a probable human carcinogen that is present in several heat-treated foods. In epidemiological studies, positive associations between dietary acrylamide intake and the risks of endometrial, ovarian, estrogen receptor-positive breast, and renal cell cancers have been observed. The association between dietary acrylamide intake and lung cancer risk is not known. We conducted a case-cohort study among 58 279 men and 62 573 women (aged 55-69 years) in the Netherlands Cohort Study on Diet and Cancer. Intakes of acrylamide-containing foods and risk factors for cancer were assessed with a self-administered questionnaire at baseline in 1986 and combined with acrylamide levels in relevant Dutch foods to assess total dietary acrylamide intake. The number of person-years at risk was estimated by using a random sample of participants from the total cohort that was chosen at baseline (n = 5000). Incident lung cancer cases in the total cohort were detected by computerized record linkages to the Netherlands Cancer Registry and the Netherlands Pathology Registry. Hazard ratios and 95% confidence intervals (CIs) for the risk of lung cancer associated with acrylamide intakes were estimated using Cox proportional hazards models that controlled for smoking (status, quantity, and duration) and other lung cancer risk factors. All statistical tests were two-sided. After 13.3 years of follow-up (September 17, 1986 up to January 1, 2000) there were 2649 cases of primary, histologically verified lung cancer (International Classification of Diseases for Oncology-3 code: C34) when cases with prevalent cancer at baseline (other than skin cancer) were excluded. The multivariable-adjusted hazard ratio of lung cancer for a 10-microg/d increment of acrylamide intake was 1.03 (95% CI = 0.96 to 1.11) for men and 0.82 (95% CI = 0.69 to 0.96) for women. The hazard ratio of lung cancer for the highest (median intake [microg/d]: men = 37.6 and women = 36.8) vs the lowest (median intake [microg/d]: men = 10.8 and women = 9.5) quintile of acrylamide intake was 1.03 (95% CI = 0.77 to 1.39, P(trend) = .85) for men and 0.45 (95% CI = 0.27 to 0.76, P(trend) = .01) for women. The inverse association in women was strongest for adenocarcinoma (hazard ratio for highest vs lowest tertile of intake = 0.40, 95% CI = 0.21 to 0.78; P(trend) = .01). Acrylamide intake was not associated with lung cancer risk in men but was inversely associated in women, most strongly for adenocarcinoma. This finding suggests that acrylamide is involved in human carcinogenesis through pathways other than genotoxicity.
    CancerSpectrum Knowledge Environment 05/2009; 101(9):651-62. · 14.07 Impact Factor
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    ABSTRACT: Arachidonic acid (AA) is considered essential in fetal development and some of its metabolites are thought to be important mediators of the immune responses. Therefore, we studied whether prenatal exposure to AA is associated with some immune-related clinical conditions and plasma markers in childhood. In 280 children aged 7 years, atopy, lung function and plasma inflammation markers were measured and their relationships with early AA exposure were studied by linear and logistic regression analyses. AA exposure was deduced from AA concentrations in plasma phospholipids of the mothers collected at several time points during pregnancy and at delivery, and in umbilical cord plasma and arterial and venous wall phospholipids. In unadjusted regression analyses, significant positive associations were observed between maternal AA concentrations at 16 and 32 weeks of pregnancy (proxies for fetal AA exposure) and peak expiratory flow decline after maximal physical exercise and plasma fibrinogen concentrations of their children, respectively. However, after correction for relevant covariables, only trends remained. A significant negative relationship was observed between AA concentrations in cord plasma (reflecting prenatal AA exposure) and the average daily amplitude of peak expiratory flow at rest, which lost significance after appropriate adjustment. Because of these few, weak and inconsistent relationships, a major impact of early-life exposure to AA on atopy, lung function and selected plasma inflammation markers of children at 7 years of age seems unlikely.
    The British journal of nutrition 02/2009; 102(3):387-97. · 3.45 Impact Factor
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    ABSTRACT: Acrylamide is a probable human carcinogen that was detected in several heat-treated foods, such as French fries and crisps, in 2002. Prospective studies are needed on acrylamide and human cancer risk. We prospectively investigated the association between acrylamide and gastrointestinal cancer risk. In 1986, 120,852 men and women (aged 55-69 y) were included in the Netherlands Cohort Study on diet and cancer. At baseline, a random subcohort of 5000 participants was selected for a case-cohort approach. Acrylamide intake was assessed with a FFQ at baseline and was based on acrylamide analyses in relevant Dutch foods. After 13.3 y of follow-up, 2190, 563, 349, and 216 cases of colorectal, gastric, pancreatic, and esophageal cancer, respectively, were available for analysis. The daily acrylamide intake of the subcohort was (mean +/- SD) 21.7 +/- 12.1 microg. A 10-microg/d increment of acrylamide intake was associated with multivariable-adjusted Cox proportional hazard rate ratios (HR) (95% CI) of 1.00 (0.96-1.06), 1.02 (0.94-1.10), 1.06 (0.96-1.17), and 0.96 (0.85-1.09) for colorectal, gastric, pancreatic, and esophageal cancer, respectively. For former or never-smokers, the corresponding HR were: 1.03 (0.94-1.12), 1.09 (0.98-1.22), 1.07 (0.93-1.24), and 0.92 (0.76-1.11). There were some significantly increased risks within subgroups stratified by obesity, nonoccupational physical activity, and age, factors that were a priori selected based on their capacity to modify cytochrome P4502E1 activity. Overall, acrylamide intake was not associated with colorectal, gastric, pancreatic, and esophageal cancer risk, but some subgroups deserve further attention.
    Journal of Nutrition 12/2008; 138(11):2229-36. · 4.20 Impact Factor
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    ABSTRACT: Acrylamide, a probable human carcinogen, was recently detected in various heat-treated carbohydrate-rich foods. Epidemiologic studies on the relation with cancer have been few and largely negative. We aimed to prospectively examine the association between dietary acrylamide intake and renal cell, bladder, and prostate cancers. The Netherlands Cohort Study on diet and cancer includes 120,852 men and women aged 55-69 y. At baseline (1986), a random subcohort of 5000 participants was selected for a case-cohort analysis approach using Cox proportional hazards analysis. Acrylamide intake was assessed with a food-frequency questionnaire at baseline and was based on chemical analysis of all relevant Dutch foods. After 13.3 y of follow-up, 339, 1210, and 2246 cases of renal cell, bladder, and prostate cancer, respectively, were available for analysis. Compared with the lowest quintile of acrylamide intake (mean intake: 9.5 microg/d), multivariable-adjusted hazard rates for renal cell, bladder, and prostate cancer in the highest quintile (mean intake: 40.8 microg/d) were 1.59 (95% CI: 1.09, 2.30; P for trend = 0.04), 0.91 (95% CI: 0.73, 1.15; P for trend = 0.60), and 1.06 (95% CI: 0.87, 1.30; P for trend = 0.69), respectively. There was an inverse nonsignificant trend for advanced prostate cancer in never smokers. We found some indications for a positive association between dietary acrylamide and renal cell cancer risk. There were no positive associations with bladder and prostate cancer risk.
    American Journal of Clinical Nutrition 06/2008; 87(5):1428-38. · 6.50 Impact Factor
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    ABSTRACT: Acrylamide, a probable human carcinogen, was detected in various heat-treated carbohydrate-rich foods in 2002. The few epidemiologic studies done thus far have not shown a relationship with cancer. Our aim was to investigate the association between acrylamide intake and endometrial, ovarian, and breast cancer risk. The Netherlands Cohort Study on diet and cancer includes 62,573 women, aged 55-69 years. At baseline (1986), a random subcohort of 2,589 women was selected using a case cohort analysis approach for analysis. The acrylamide intake of subcohort members and cases was assessed with a food frequency questionnaire and was based on chemical analysis of all relevant Dutch foods. Subgroup analyses were done for never-smokers to eliminate the influence of smoking; an important source of acrylamide. After 11.3 years of follow-up, 327, 300, and 1,835 cases of endometrial, ovarian, and breast cancer, respectively, were documented. Compared with the lowest quintile of acrylamide intake (mean intake, 8.9 mug/day), multivariable-adjusted hazard rate ratios (HR) for endometrial, ovarian, and breast cancer in the highest quintile (mean intake, 40.2 mug/day) were 1.29 [95% confidence interval (95% CI), 0.81-2.07; P(trend)=0.18], 1.78 (95% CI, 1.10-2.88; P(trend)=0.02), and 0.93 (95% CI, 0.73-1.19; P(trend)=0.79), respectively. For never-smokers, the corresponding HRs were 1.99 (95% CI, 1.12-3.52; P(trend)=0.03), 2.22 (95% CI, 1.20-4.08; P(trend)=0.01), and 1.10 (95% CI, 0.80-1.52; P(trend)=0.55). We observed increased risks of postmenopausal endometrial and ovarian cancer with increasing dietary acrylamide intake, particularly among never-smokers. Risk of breast cancer was not associated with acrylamide intake.
    Cancer Epidemiology Biomarkers &amp Prevention 12/2007; 16(11):2304-13. · 4.56 Impact Factor
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    Clinical Chemistry 07/2007; 53(6):1168-70. · 7.15 Impact Factor
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    ABSTRACT: Particulate air pollution (PM) is an important environmental health risk factor for many different diseases. This is indicated by numerous epidemiological studies on associations between PM exposure and occurrence of acute respiratory infections, lung cancer and chronic respiratory and cardiovascular diseases. The biological mechanisms behind these associations are not fully understood, but the results of in vitro toxicological research have shown that PM induces several types of adverse cellular effects, including cytotoxicity, mutagenicity, DNA damage and stimulation of proinflammatory cytokine production. Because traffic is an important source of PM emission, it seems obvious that traffic intensity has an important impact on both quantitative and qualitative aspects of ambient PM, including its chemical, physical and toxicological characteristics. In this review, the results are summarized of the most recent studies investigating physical and chemical characteristics of ambient and traffic-related PM in relation to its toxicological activity. This evaluation shows that, in general, the smaller PM size fractions (<PM(10)) have the highest toxicity, contain higher concentrations of extractable organic matter (comprising a wide spectrum of chemical substances), and possess a relatively high radical-generating capacity. Also, associations between chemical characteristics and PM toxicity tend to be stronger for the smaller PM size fractions. Most importantly, traffic intensity does not always explain local differences in PM toxicity, and these differences are not necessarily related to PM mass concentrations. This implies that PM regulatory strategies should take PM-size fractions smaller than PM(10) into account. Therefore, future research should aim at establishing the relationship between toxicity of these smaller fractions in relation to their specific sources.
    Mutation Research/Fundamental and Molecular Mechanisms of Mutagenesis 11/2006; 613(2-3):103-22. · 3.90 Impact Factor
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    ABSTRACT: To determine whether or not there is a relationship between the lung function of school children and the ability of fine dust particles in the air to generate radicals. Descriptive. Six primary schools in locations with different traffic volumes were selected in Maastricht, the Netherlands. Air samples were taken in these schools over a period of 4 days; the concentration of fine dust was measured in the 6 pooled samples. Lung function tests were performed in children in the age of 8-13 and their parents filled out a questionnaire on the state of their children's health. An average of 66% of the children (184 girls and 158 boys, with an average age of 10 years (range: 8-13 years)) participated. The average FEV1 for the children from the 6 schools was not related with the total amount of fine dust particles in the air. However, a lower average FEV1 was associated with a higher radical-generating capacity in the air samples. No direct association was observed between the radical-generating capacity of the dust and the traffic intensity. There was a clear relationship between lung function and the radical-generating capacity of fine dust in the air. On the basis of these findings future guidelines could be based on chemical properties of the fine dust particles and not exclusively on the quantity of fine dust.
    Nederlands tijdschrift voor geneeskunde 05/2006; 150(13):735-40.