Mostafalou and Abdollahi, 2017

Sara Mostafalou and Mohammad Abdollahi, “Pesticides: an update of human exposure and toxicity,” Archives of Toxicology, February 2017, 91:2, DOI: 10.1007/s00204-016-1849-x.

ABSTRACT:

Pesticides are a family of compounds which have brought many benefits to mankind in the agricultural, industrial, and health areas, but their toxicities in both humans and animals have always been a concern. Regardless of acute poisonings which are common for some classes of pesticides like organophosphoruses, the association of chronic and sub-lethal exposure to pesticides with a prevalence of some persistent diseases is going to be a phenomenon to which global attention has been attracted. In this review, incidence of various malignant, neurodegenerative, respiratory, reproductive, developmental, and metabolic diseases in relation to different routes of human exposure to pesticides such as occupational, environmental, residential, parental, maternal, and paternal has been systematically criticized in different categories of pesticide toxicities like carcinogenicity, neurotoxicity, pulmonotoxicity, reproductive toxicity, developmental toxicity, and metabolic toxicity. A huge body of evidence exists on the possible role of pesticide exposures in the elevated incidence of human diseases such as cancers, Alzheimer, Parkinson, amyotrophic lateral sclerosis, asthma, bronchitis, infertility, birth defects, attention deficit hyperactivity disorder, autism, diabetes, and obesity. Most of the disorders are induced by insecticides and herbicides most notably organophosphorus, organochlorines, phenoxyacetic acids, and triazine compounds.

Islam et al., 2018

Faisal Islam, Jian Wang, Muhammad A. Farooq, Muhammad S.S. Khan, Ling Xu, Jinwen Zhu, Min Zhao, Stéphane Muños, Qing X. Li, Weijun Zhou, “Potential impact of the herbicide 2,4-dichlorophenoxyacetic acid on human and ecosystems,” Environment International, 2018, 111, DOI: 10.1016/j.envint.2017.10.020.

ABSRACT: The herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) is applied directly to aquatic and conventional farming systems to control weeds, and is among the most widely distributed pollutants in the environment. Non-target organisms are exposed to 2,4-D via several ways, which could produce toxic effects depending on the dose, frequency of exposure, and the host factors that influence susceptibility and sensitivity. An increasing number of experimental evidences have shown concerns about its presence/detection in the environment, because several investigations have pointed out its potential lethal effects on non-target organisms. In this review, we critically evaluated the environmental fate and behavior of 2,4-D along with its eco-toxicological effects on aquatic, plants and human life to provide concise assessment in the light of recently published reports. The findings demonstrate that 2,4-D is present in a low concentration in surface water of regions where its usage is high. The highest concentrations of 2,4-D were detected in soil, air and surface water surrounded by crop fields, which suggest that mitigation strategies must be implanted locally to prevent the entry of 2,4-D into the environment. A general public may have frequent exposure to 2,4-D due to its wide applications at home lawns and public parks, etc. Various in vivo and in vitro investigations suggest that several species (or their organs) at different trophic levels are extremely sensitive to the 2,4-D exposure, which may explain variation in outcomes of reported investigations. However, implications for the prenatal exposure to 2,4-D remain unknown because 2,4-D-induced toxicity thresholds in organism have only been derived from juveniles or adults. In near future, introduction of 2,4-D resistant crops will increase its use in agriculture, which may cause relatively high and potentially unsafe residue levels in the environment. The recent findings indicate the urgent need to further explore fate, accumulation and its continuous low level exposure impacts on the environment to generate reliable database which is key in drafting new regulation and policies to protect the population from further exposure.

Schütte et al., 2017

Gesine Schütte, Michael Eckerstorfer, Valentina Rastelli, Wolfram Reichenbecher, Sara Restrepo‑Vassalli, Marja Ruohonen‑Lehto, Anne‑Gabrielle Wuest Saucy, and Martha Mertens, “Herbicide resistance and biodiversity: agronomic and environmental aspects of genetically modified herbicide-resistant plants,” Environmental Sciences Europe, 2017, 29:5, DOI: 10.1186/s12302-016-0100-y.

ABSTRACT:

Farmland biodiversity is an important characteristic when assessing sustainability of agricultural practices and is of major international concern. Scientific data indicate that agricultural intensification and pesticide use are among the main drivers of biodiversity loss. The analysed data and experiences do not support statements that herbicide-resistant crops provide consistently better yields than conventional crops or reduce herbicide amounts. They rather show that the adoption of herbicide-resistant crops impacts agronomy, agricultural practice, and weed management and contributes to biodiversity loss in several ways: (i) many studies show that glyphosate-based herbicides, which were commonly regarded as less harmful, are toxic to a range of aquatic organisms and adversely affect the soil and intestinal microflora and plant disease resistance; the increased use of 2,4-D or dicamba, linked to new herbicide-resistant crops, causes special concerns. (ii) The adoption of herbicide-resistant crops has reduced crop rotation and favoured weed management that is solely based on the use of herbicides. (iii) Continuous herbicide resistance cropping and the intensive use of glyphosate over the last 20 years have led to the appearance of at least 34 glyphosate-resistant weed species worldwide. Although recommended for many years, farmers did not counter resistance development in weeds by integrated weed management, but continued to rely on herbicides as sole measure. Despite occurrence of widespread resistance in weeds to other herbicides, industry rather develops transgenic crops with additional herbicide resistance genes. (iv) Agricultural management based on broad-spectrum herbicides as in herbicide-resistant crops further decreases diversity and abundance of wild plants and impacts arthropod fauna and other farmland animals. Taken together, adverse impacts of herbicide-resistant crops on biodiversity, when widely adopted, should be expected and are indeed very hard to avoid. For that reason, and in order to comply with international agreements to protect and enhance biodiversity, agriculture needs to focus on practices that are more environmentally friendly, including an overall reduction in pesticide use. (Pesticides are used for agricultural as well non-agricultural purposes. Most commonly they are used as plant protection products and regarded as a synonym for it and so also in this text.) FULL TEXT

Marouani et al., 2017

Neila Marouani, Olfa Tebourbi, Donia Cherif, Dorsaf Hallegue, Mohamed Tahar Yacoubi, Mohsen Sakly, Moncef Benkhalifa, Khemais Ben Rhouma, “Effects of oral administration of 2,4-dichlorophenoxyacetic acid (2,4-D) on reproductive parameters in male Wistar rats,” Environmental Science and Pollution Research, January 2017, Volume 24:1, DOI: 10.1007/s11356-016-7656-3.

ABSTRACT:

The 2,4-dichlorophenoxyacetic acid (2,4-D) is used worldwide in agriculture as a selective herbicide. It has been shown to produce a wide range of adverse effects on the health of both animals and humans from embryotoxicity and teratogenicity to neurotoxicity. In the present study, we have examined the effect of 2,4-D on male reproductive function of rats. Male Wistar rats received daily by force-feeding 100 or 200 mg of 2,4-D/kg body weight for 30 consecutive days. Rats exposed to 100 and 200 mg of 2,4-D/kg showed a significant decrease in body weights only after 24 days of treatment and in relative weights of testis, seminal vesicles and prostate at killing day, when compared with controls. Moreover, a decrease in testosterone and an increase in FSH and LH serum levels were detected in treated rats. Besides, exposure to this herbicide induced pronounced testicular histological alterations with enlarged intracellular spaces, tissue loosening and dramatic loss of gametes in the lumen of the seminiferous tubules. In addition, a decreased motility and a number of epididymal spermatozoa with an increased sperm abnormality rate were found in treated rats in comparison with control. With the highest dose, histological observations of seminal vesicles indicated a considerable decrease of secretions in the lumen, a thinness of the muscle layer surrounding the epithelium with branched mucosal crypts and reduced luminal space. In prostate, the heights of the cells decreased while acinar lumen were enlarged and they lost the typical invaginations. Our results suggest that a subacute treatment of 2,4-D promotes reproductive system toxicity.

Eskenazi et al., 2004

Brenda Eskenazi, Kim Harley, Asa Bradman, Erin Weltzien, Nicholas P. Jewell, Dana B. Barr, Clement E. Furlong, and Nina T. Holland, “Association of in Utero Organophosphate Pesticide Exposure and Fetal Growth and Length of Gestation in an Agricultural Population,” Environmental Health Perspecitives, 112:10, 2004, DOI: 10.1289/ehp.6789

ABSTRACT:

Although pesticide use is widespread, little is known about potential adverse health effects of in utero exposure. We investigated the effects of  organophosphate pesticide exposure during pregnancy on fetal growth and gestational duration in a cohort of low-income, Latina women living in an agricultural community in the Salinas Valley, California. We measured nonspecific metabolites of organophosphate pesticides (dimethyl and diethyl phosphates) and metabolites specific to malathion (malathion dicarboxylic acid), chlorpyrifos [O,O-diethyl O-(3,5,6-trichloro-2-pyridinyl) phosphoro-thioate], and parathion (4-nitrophenol) in maternal urine collected twice during pregnancy. We also measured levels of cholinesterase in whole blood and butyryl cholinesterase in plasma in maternal and umbilical cord blood. We failed to demonstrate an adverse relationship between fetal growth and any measure of in utero organophosphate pesticide exposure. In fact, we found increases in body length and head circumference associated with some exposure measures.
However, we did find decreases in gestational duration associated with two measures of in utero pesticide exposure: urinary dimethyl phosphate metabolites [βadjusted = –0.41 weeks per log10 unit increase; 95% confidence interval (CI), –0.75––0.02; p = 0.02], which reflect exposure to dimethyl organophosphate compounds such as malathion, and umbilical cord cholinesterase (βadjusted = 0.34 weeks per unit increase; 95% CI, 0.13–0.55; p = 0.001). Shortened gestational duration was most clearly related to increasing exposure levels in the latter part of pregnancy. These associations with gestational age may be biologically plausible given that organophosphate pesticides depress cholinesterase and acetylcholine stimulates contraction of the uterus. However, despite these observed associations, the rate of preterm delivery in this population (6.4%) was lower than in a U.S. reference population.   FULL TEXT

Goldman et al., 2004

Goldman L1, Eskenazi B, Bradman A, Jewell NP., “Risk behaviors for pesticide exposure among pregnant women living in farmworker households in Salinas, California,”  American Journal of Industrial Medicine, 45:6, 2004, DOI: 10.1002/ajim.20012

ABSTRACT:

BACKGROUND: Farmworkers and their families are at risk for pesticide exposure, however, little is known about behaviors that increase their risk. We determined the frequency of risky behaviors among pregnant farmworkers and characterized those at greatest risk.

METHODS: Participants included 153 pregnant farmworkers and 248 pregnant non-farmworkers who resided with farmworkers from the CHAMACOS (Center for the Health Assessment of Mothers and Children of Salinas) study. We examined risky behaviors relating to handwashing, bathing, protective clothing, house cleaning, laundering of work clothes, wearing of work clothes and shoes into the home, and eating produce from the fields.

RESULTS: Between 25 and 60% of women demonstrated risky behavior on each item. Practices of households with pregnant farmworkers and non-farmworkers did not differ. Women who lived in the United States longer, and in crowded households demonstrated the most risky behavior overall.

CONCLUSIONS: Pregnant farmworkers and those living with farmworkers need to be educated to reduce potential take-home pesticide exposure.

Ranjbar et al., 2015

Mahsa Ranjbar, Michael A. Rotondi, Chris I. Ardern, and Jennifer L. Kuk, “The Influence of Urinary Concentrations of Organophosphate Metabolites on the Relationship between BMI and Cardiometabolic Health Risk,” Journal of Obesity, 2015, DOI: 10.1155/2015/687914

ABSTRACT:

The objective was to determine whether detectable levels of OP metabolites influence the relationship between BMI and cardiometabolic health. This cross-sectional study was conducted using 2227 adults from the 1999–2008 NHANES datasets.  Urinary concentrations of six dialkyl phosphate metabolites were dichotomized to above and below the detection limit. Weighted multiple regression analysis was performed adjusting for confounding variables. Independent of BMI, individuals with detectable metabolites had higher diastolic blood pressure (for dimethylphosphate, diethylphosphate, and diethyldithiophosphate; ???? < 0.05), lower HDL (for diethyldithiophosphate; ???? = 0.02), and higher triglyceride (for dimethyldithiophosphate; ???? = 0.05) than those below detection. Contrarily, those with detectable dimethylthiophosphate had better LDL, HDL, and total cholesterol, independent of BMI. Individuals at a higher BMI range who had detectable diethylphosphate (interaction: ???? = 0.03) and diethylthiophosphate (interaction: ???? = 0.02) exhibited lower HDL, while little difference existed between OP metabolite detection statuses at lower BMIs.  Similarly, individuals with high BMIs and detectable diethylphosphate had higher triglyceride than those without detectable levels, while minimal differences between diethylphosphate detection statuses were observed at lower BMIs (interaction: ???? = 0.02). Thus, cardiometabolic health outcome differs depending on the specific OP metabolite being examined, with higher BMIs amplifying health risk.  FULL TEXT

Tsao et al., 2016

Yun-Chen Tsao, Yung-Chun Lai, Hsiu-Chuan Liu, Ray H. Liu, and Dong-Liang Lin, “Simultaneous Determination and Quantitation of Paraquat, Diquat, Glufosinate and Glyphosate,in Postmortem Blood and Urine by LC–MS-MS,” Journal of Analytical Toxicology, 40, 2016, DOI: 10.1093/jat/bkw042

ABSTRACT:

A simple method, incorporating protein-precipitation/organic backwashing and liquid chromatography–tandem mass spectrometry (LC–MS-MS), has been successfully developed for the simultaneous analysis of four highly water-soluble and less volatile herbicides (paraquat, diquat, glufosinate and glyphosate) in ante- and postmortem blood, urine and gastric content samples. Respective isotopically labeled analogs of these analytes were adopted as internal standards.  Acetonitrile and dichloromethane were used for protein precipitation and organic solvent backwashing, respectively, followed by injecting the upper aqueous phase into the LC–MS-MS system. Chromatographic separation was achieved using an Agilent Zorbax SB-Aq analytical column, with gradient elution of 15 mM heptafluorobutyric acid and acetonitrile. Mass spectrometric analysis was performed under electrospray ionization in positive-ion multiple reaction
monitoring mode. The precursor ions and the two transition ions (m/z) adopted for each of these four analytes were paraquat (185; 169 and 115), diquat (183; 157 and 78), glufosinate (182; 136 and 119) and glyphosate (170; 88 and 60), respectively. Analyte-free blood and urine samples, fortified with the analytes of  interest, were used for method development/validation and yielded acceptable recoveries of the analytes; interday and intraday precision and accuracy data; calibration linearity and limits of detection and quantitation. This method was successfully incorporated into an overall analytical scheme, designed for the analysis of a broad range of compounds present in postmortem samples, helpful to medical examiners’ efforts to determine victims’ causes of death. FULL TEXT

Brändli et al., 2012

Dirk Brändli and Sandra Reinacher, “Herbicides found in Human Urine,” Ithaka Journal, 1/2012, 2012

SUMMARY:

Glyphosate is the main active substance used in most commercial herbicides. It poisons not only plants, but also animals and humans. When testing for glyphosate contamination in an urban population, a German university found significant contamination in all urine samples with levels 5 to 20 times above the legal limit for drinking water.  Glyphosate background info, health risks, and reasons for contamination are discussed.  FULL TEXT

Curwin et al., 2007

Brian Curwin, Misty Hein, Wayne Sanderson, Cynthia Striley, Dick Heederik, Hans Kromhout, Stephen Reynolds, Michael Alavanja, “Urinary Pesticide Concentrations Among Children, Mothers and Fathers Living in Farm and Non-Farm Households in Iowa,” The Annals of Occupational Hygiene, 51:1, January 2007, DOI: 10.1093/annhyg/mel062

ABSTRACT: