Characteristics and magnitude of acute pesticide-related illnesses and injuries associated with pyrethrin and pyrethroid exposures--11 states, 2000-2008

Association of pesticide exposure with respiratory health outcomes and rhinitis in avocado farmworkers from Michoacán, Mexico

BACKGROUND

A growing literature suggests associations between occupational pesticide exposure and respiratory health. In this study, we aimed to examine the association of exposure to insecticides, fungicides, and herbicides, individually and as a mixture, with respiratory health outcomes and rhinitis in avocado farmworkers from Michoacán, Mexico.

MATERIAL AND METHODS

We conducted a cross-sectional study of 105 avocado farmworkers between May and August 2021. We quantified 12 insecticide, fungicide, and herbicide metabolites in urine samples collected during two study visits (8-10 weeks apart). We collected survey data on self-reported pesticide use during the 12 months prior to the baseline survey and estimated annual exposure-intensity scores (EIS) using a semi-quantitative exposure algorithm. We also assessed respiratory symptoms, including wheezing, chest tightness, wheezing after exercise, and night cough. We used generalized linear regression models to examine associations of individual urinary metabolite concentrations and annual EIS with respiratory health outcomes and rhinitis. Mixture effects were assessed using Bayesian Weighted Quantile Sum (BWQS) regression.

RESULTS

After adjusting for multiple comparisons, we observed mostly null associations of individual pesticide metabolite concentrations and annual EIS with the outcomes of interest. However, in BWQS analyses, we found evidence of a mixture association of urinary pesticide metabolites with increased odds of night cough (OR: 5.34, 95 % CrI: 1.67, 20.62). Pyrethroid metabolites 3-phenoxybenzoic acid and cis- and trans-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropanecarboxylic acid were the main contributors to this association (43 %).

CONCLUSIONS

Our findings indicate that exposure to a mixture of pesticides, particularly pyrethroid insecticides, may be associated with night cough in avocado farmworkers.

Placental transcriptome variation associated with season, location, and urinary prenatal pyrethroid metabolites of Thai farm-working women

Prenatal exposure to pyrethroids is linked to adverse health effects in early life and proper placental function is critical to fetal development. This study explores the impact of prenatal pyrethroid exposure, as well as factors impacting exposure and effect, on the placental transcriptome, to understand pyrethroid exposures' relationship to placental function. The study of Asian Women and their Offspring's Development and Environmental Exposures (SAWASDEE) recruited pregnant farm-working women from two agricultural districts in the Chiang Mai province of Thailand between 2017 and 2019. This cohort was predominantly exposed to cypermethrin (type II), alongside pyrethroids such as cyfluthrin (type II) and permethrin (type I). In 253 participants, maternal urinary pyrethroid metabolites, 3-phenoxybenzoic acid (PBA), cis-3-(2,2-Dichlorovinyl)-2,2-dimethylcyclopropane carboxylic acid (CDCCA), and trans-3-(2,2-Dichlorovinyl)-2,2-dimethylcyclopropane carboxylic acid (TDCCA) were measured in early, middle, and late pregnancy and adjusted for urinary creatinine. The placental transcriptome was analyzed using RNA-Seq. Using generalized linear regression, we identified differentially expressed genes (DEGs) associated with the sum of each metabolite across pregnancy, as well as those associated with location of residence and season of birth. Pathway and upstream transcription factor analyses were performed to examine potential mechanisms associated with DEGs. Notably, TDCCA and CDCCA levels peaked in late pregnancy, with significant regional differences, particularly higher levels in the Fang region. Placental gene expression analysis showed no DEGs associated with individual metabolites at FDR<0.05. However, 251 DEGs by location, implicating immune response and oxidative phosphorylation pathways, were identified, while season of birth was associated with 2585 DEGs, over-represented in fibrosis signaling and metabolism pathways. Finally, transcription factor analysis identified 226 and 282 transcription factors associated with location and season, respectively, related to cell proliferation, differentiation, and the immune system. These alterations may have significant implications for fetal development and other pathologic processes, highlighting the importance of monitoring environmental exposures during pregnancy.

TFOS Lifestyle Report: Impact of environmental conditions on the ocular surface

Environmental risk factors that have an impact on the ocular surface were reviewed and associations with age and sex, race/ethnicity, geographical area, seasonality, prevalence and possible interactions between risk factors are reviewed. Environmental factors can be (a) climate-related: temperature, humidity, wind speed, altitude, dew point, ultraviolet light, and allergen or (b) outdoor and indoor pollution: gases, particulate matter, and other sources of airborne pollutants. Temperature affects ocular surface homeostasis directly and indirectly, precipitating ocular surface diseases and/or symptoms, including trachoma. Humidity is negatively associated with dry eye disease. There is little data on wind speed and dewpoint. High altitude and ultraviolet light exposure are associated with pterygium, ocular surface degenerations and neoplastic disease. Pollution is associated with dry eye disease and conjunctivitis. Primary Sjögren syndrome is associated with exposure to chemical solvents. Living within a potential zone of active volcanic eruption is associated with eye irritation. Indoor pollution, "sick" building or house can also be associated with eye irritation. Most ocular surface conditions are multifactorial, and several environmental factors may contribute to specific diseases. A systematic review was conducted to answer the following research question: "What are the associations between outdoor environment pollution and signs or symptoms of dry eye disease in humans?" Dry eye disease is associated with air pollution (from NO2) and soil pollution (from chromium), but not from air pollution from CO or PM10. Future research should adequately account for confounders, follow up over time, and report results separately for ocular surface findings, including signs and symptoms.

Acute Pesticide Poisoning in Tobacco Farming, According to Different Criteria

BACKGROUND

Brazil is one of the world's largest pesticide consumers, but information on pesticide poisoning among workers is scarce.

OBJECTIVE

To evaluate acute pesticide poisoning among tobacco growers, according to different criteria.

METHODS

This was a two-step cross-sectional study with 492 pesticide applicators. It used a 25 question pesticide-related symptoms (PRS) questionnaire and medical diagnosis for comparison with toxicological assessment. Associations were evaluated using Poisson regression.

RESULTS

10.6% reported two or more PRS, while 8.1% reported three or more. Furthermore, 12.2% received a medical diagnosis of poisoning. According to toxicologists, possible cases accounted for 14.2% and probable cases for 4.3%. PRS increased during the period of greater exposure. Those exposed to dithiocarbamates, sulfentrazone, pyrethroids, fipronil and iprodione exhibited more PRS. The number of exposure types, multi-chemical exposure, clothes wet with pesticides and spillage on the body/clothes were associated with acute poisonings. All criteria showed sensitivity greater than 79% for probable cases but only greater than 70% for medical diagnosis when compared to possible cases, presenting substantial Kappa agreement.

CONCLUSION

The prevalence of acute pesticide poisoning is much higher than officially recorded. Trained physicians can screen for pesticide poisoning. It is necessary to improve workers' education to reduce pesticide use and exposure to them.

Evaluating wipe sampling parameters to assess method performance and data confidence during remediation of hazardous pesticide misuse chemicals on indoor materials

Pesticide misuse incidents are reported worldwide each year. The potential exposure to pesticides creates a concern for occupants in affected homes, apartments, and other occupied buildings. Pesticides that are improperly applied within these locations may require remediation prior to reoccupation. Incident response personnel rely heavily on data from sampling results to identify residue levels and determine when site remediation is complete. Surface wipe samples are often collected for this purpose. Therefore, it is important to ensure sampling and analysis procedures are well established for the contaminants of concern, particularly for wipe sampling variables that can affect analysis results. This investigation evaluated the effects of surface wipe media, wipe wetting solvents, pesticide concentrations effects, composite sampling, surface types, and pesticide formulation effects on analysis results for fipronil, permethrin, and deltamethrin. Tested surface types included galvanized steel, vinyl tile, and plywood. Wipe media included pre-packaged, sterile cotton gauze, pre-cleaned cotton twill, and a pre-packaged, pre-wetted wipes. Surface recovery results are reported for commercially available fipronil formulations and compared to technical grade fipronil solutions. Fipronil recoveries were 92-107 % for twill wipes, 81-98 % for cotton gauze wipes, and 79 % for pre-packaged, pre-wetted wipes on a galvanized steel surface. Permethrin recoveries were 83-116 % for twill wipes, 66-94 % for cotton gauze wipes, and 73 % for pre-packaged, pre-wetted wipes on a galvanized steel surface. Deltamethrin recoveries were 67-88 % for twill wipes, 55-71 % for cotton gauze wipes, and 63 % for pre-packaged, pre-wetted wipes on a galvanized steel surface. The data collected in this study can inform surface wipe sampling methods and potentially assist in obtaining more accurate sampling data associated with pesticide misuse incidents involving the target analytes.

Current status of pesticide effects on environment, human health and it's eco-friendly management as bioremediation: A comprehensive review

Pesticides are either natural or chemically synthesized compounds that are used to control a variety of pests. These chemical compounds are used in a variety of sectors like food, forestry, agriculture and aquaculture. Pesticides shows their toxicity into the living systems. The World Health Organization (WHO) categorizes them based on their detrimental effects, emphasizing the relevance of public health. The usage can be minimized to a least level by using them sparingly with a complete grasp of their categorization, which is beneficial to both human health and the environment. In this review, we have discussed pesticides with respect to their global scenarios, such as worldwide distribution and environmental impacts. Major literature focused on potential uses of pesticides, classification according to their properties and toxicity and their adverse effect on natural system (soil and aquatic), water, plants (growth, metabolism, genotypic and phenotypic changes and impact on plants defense system), human health (genetic alteration, cancer, allergies, and asthma), and preserve food products. We have also described eco-friendly management strategies for pesticides as a green solution, including bacterial degradation, myco-remediation, phytoremediation, and microalgae-based bioremediation. The microbes, using catabolic enzymes for degradation of pesticides and clean-up from the environment. This review shows the importance of finding potent microbes, novel genes, and biotechnological applications for pesticide waste management to create a sustainable environment.

Retrospective analysis of adverse effects associated with pyrethrins-containing products

The Pyrethrins Stewardship Program (PSP) was established to better understand adverse effects following exposure to pyrethrins-containing insecticide products. Running from April 2010 through December 2016, symptomatic dermal and inhalation exposures were entered into Phase I of the PSP and analyzed for exposure details and nature of the effects reported. Phase II consisted of an in-depth telephone interview using an enhanced questionnaire to investigate additional exposure details. Phase III scored the association between exposure and reported effects. Based on the data collected and analyzed, we conclude that: (1) Both in absolute number and relative to the wide distribution and use by consumers, adverse respiratory or dermal events after product exposure were rare; (2) Most outcomes for the reported events involving either dermal or respiratory effects were of minor severity and self-limiting; (3) None of the data collected and analyzed indicate that pyrethrins-containing products, including those formulated with synthetic pyrethroids and/or synergists, pose a significant risk of serious dermal or respiratory reactions even in cases where the exposed individual reported having allergies or asthma; (4) No additional label warnings or other mitigation techniques are warranted with pyrethrins-containing products formulated with or without synthetic pyrethroids and/or synergists.

Bioremediation role of Spirulina platensis against deltamethrin-mediated toxicity and its chemical residues in chicken meat

Deltamethrin (DM) is a synthetic pyrethroid insecticide commonly used in veterinary and agriculture. However, both animal and human exposure are associated with hepatorenal toxicity. Our experimental goal was to assess the protective effects of Spirulina platensis (SP) against DM-induced hepatorenal injury, growth performance, meat chemical composition, and its residues in meat, liver, and skin of broiler chickens. Sixty 1-day-old Cobb broiler chicks were assigned to 4 experimental groups; each was divided into 3 replicates with five chicks each; the 1st group received basal diet alone (control), 2nd group supplemented with SP 20 g/kg diet, 3rd group supplemented with DM 300 mg/kg diet, and 4th group supplemented with DM and SP diet. All groups have received the treatment for 35 days. DM, decreased body weight, weight gain, and increased feed conversion rate. DM showed a significant increase in ALT, AST, urea, creatinine, and MDA and a significant decrease in SOD, and GSH levels. Also, SP significantly reduced DM levels in meat, skin, and liver with a reduction 63.01, 63.00, and 62.90 %, respectively. The DM intoxicated group showed a significant decrease in protein and a marked increase in fat, cholesterol, and triglycerides when compared to the control group. Histopathological changes were also recorded. Dietary SP improved these parameters. Dietary inclusion of SP can be recommended due to the protective effects on DM-induced toxicity in broiler chickens.

Pyrethroid based pesticides - chemical and biological aspects

Human and animal welfare primarily depends on the availability of food and surrounding environment. Over a century and half, the quest to identify agents that can enhance food production and protection from vector borne diseases resulted in the identification and use of a variety of pesticides, of which the pyrethroid based ones emerged as the best choice. Pesticides while improved the quality of life, on the other hand caused enormous health risks. Because of their percolation into drinking water and food chain and usage in domestic settings, humans unintentionally get exposed to the pesticides on a daily basis. The health hazards of almost all known pesticides at a variety of doses and exposure times are reported. This review provides a comprehensive summation on the historical, epidemiological, chemical and biological (physiological, biochemical and molecular) aspects of pyrethroid based insecticides. An overview of the available knowledge suggests that the synthetic pyrethroids vary in their chemical and toxic nature and pose health hazards that range from simple nausea to cancers. Despite large number of reports, studies that focused on identifying the health hazards using doses that are equivalent or relevant to human exposure are lacking. It is high time such studies are conducted to provide concrete evidence on the hazards of consuming pesticide contaminated food. Policy decisions to decrease the residual levels of pesticides in agricultural products and also to encourage organic farming is suggested.

The global distribution of acute unintentional pesticide poisoning: estimations based on a systematic review

BACKGROUND

Human poisoning by pesticides has long been seen as a severe public health problem. As early as 1990, a task force of the World Health Organization (WHO) estimated that about one million unintentional pesticide poisonings occur annually, leading to approximately 20,000 deaths. Thirty years on there is no up-to-date picture of global pesticide poisoning despite an increase in global pesticide use. Our aim was to systematically review the prevalence of unintentional, acute pesticide poisoning (UAPP), and to estimate the annual global number of UAPP.

METHODS

We carried out a systematic review of the scientific literature published between 2006 and 2018, supplemented by mortality data from WHO. We extracted data from 157 publications and the WHO cause-of-death database, then performed country-wise synopses, and arrived at annual numbers of national UAPP. World-wide UAPP was estimated based on national figures and population data for regions defined by the Food and Agriculture Organization (FAO).

RESULTS

In total 141 countries were covered, including 58 by the 157 articles and an additional 83 by data from the WHO Mortality Database. Approximately 740,000 annual cases of UAPP were reported by the extracted publications resulting from 7446 fatalities and 733,921 non-fatal cases. On this basis, we estimate that about 385 million cases of UAPP occur annually world-wide including around 11,000 fatalities. Based on a worldwide farming population of approximately 860 million this means that about 44% of farmers are poisoned by pesticides every year. The greatest estimated number of UAPP cases is in southern Asia, followed by south-eastern Asia and east Africa with regards to non-fatal UAPP.

CONCLUSIONS

Our study updates outdated figures on world-wide UAPP. Along with other estimates, robust evidence is presented that acute pesticide poisoning is an ongoing major global public health challenge. There is a need to recognize the high burden of non-fatal UAPP, particularly on farmers and farmworkers, and that the current focus solely on fatalities hampers international efforts in risk assessment and prevention of poisoning. Implementation of the international recommendations to phase out highly hazardous pesticides by the FAO Council could significantly reduce the burden of UAPP.

Pyrethrum extract induces oxidative DNA damage and AMPK/mTOR-mediated autophagy in SH-SY5Y cells

Pyrethrum extract is used to produce the most widely applied botanical pesticides in agriculture. Though it primarily targets voltage-gated sodium channels in pests, its toxic effects in non-target systems, particularly in humans, is unclear. In this study, we investigated potential cytotoxic effects and their underlying mechanisms on human nerve cells in vitro. We found that pyrethrum extract exposure markedly inhibited cell viability and triggered oxidative DNA damage in human SH-SY5Y cells. It also induced LC3-II formation, upregulated Beclin-1 protein production, downregulated p62 protein production, and facilitated the phosphorylation of adenosine monophosphate-activated protein kinase (AMPK) and mechanistic target of rapamycin (mTOR). These results indicate that cytotoxic exposure to pyrethrum extract could be associated with AMPK/mTOR-mediated autophagy in human nerve cells. Furthermore, the oxidative DNA damage suggests that pyrethrum extract exerts severe toxic effects on human nerve cells. In conclusion, pyrethrum extract carries a risk to human health by inducing cytotoxicity.

Nontransient third-degree heart block and persistent respiratory findings as sequelae of acute occupational exposure to pyrethroids insecticide

We present the case of a worker with occupational exposure to a pyrethroid insecticide who acutely developed nontransient third-degree heart block. In 2000, a 57-year-old male truck driver on his delivery route was accidentally exposed to pyrethroid insecticide being sprayed for West Nile virus containment. Both the driver and his vehicle were coated with the spray. The exposure was prolonged because he did not change his clothes until after his shift ended and he used the same contaminated truck for a week. Within days, he presented with a third-degree heart block, for which he was emergently treated, and a pacemaker was placed. He had no past history of arrhythmias. In the weeks thereafter, he also developed reactive airway dysfunction syndrome (RADS). In the second decade following the exposure, the patient replaced his pacemaker, confirming the permanent nature of his heart block. In addition to the persistence of his exposure-related RADS, he developed restrictive lung disease and was diagnosed with pulmonary interstitial fibrosis in the absence of established risk factors. The patient died in October 2019 from respiratory illness. Most previous reports of pyrethroid-related disorders are limited to acute exposures, in which transient symptoms predominate. To our knowledge, this is the first report of an exposed worker experiencing permanent third-degree heart block, as well as persistent respiratory findings, as possible short- and long-term sequelae of pyrethroid exposure.

Urinary 3-phenoxybenzoic acid levels and the association with thyroid hormones in adults: Korean National Environmental Health Survey 2012-2014

BACKGROUND

Owing to insecticidal activity at low doses with relatively low toxicity in humans, synthetic pyrethroids have been used widely for pest control in agricultural and domestic settings. Pyrethroids are suspected for potential endocrine disruption. However, the thyroid disrupting effects of pyrethroids, particularly in humans, is relatively underexplored.

OBJECTIVES

This study aimed to report 3-phenoxybenzoic acid (3-PBA) concentrations in urine, and assess its association with serum thyroid hormone (TH) levels in a representative adult population of Korea.

METHODS

Data obtained from representative Korean adults recruited in the Korean National Environmental Health Survey (2nd round, 2012-2014) were analyzed. Urinary 3-PBA levels were associated with serum thyroxine (T4), total triiodothyronine (T3), and thyroid-stimulating hormone (TSH) levels among the Korean adult population.

RESULTS

Urinary 3-PBA levels among Korean adults were >3 times higher than those reported in Canada and the United States. Urinary 3-PBA levels showed negative association with serum T4, and this pattern was not changed after stratification by sex. For T3, the association varied by sex and exposure levels. Male demonstrated the same inverse association between urinary 3-PBA and T3, but female did not show such association. Among adults in the lower half of urinary 3-PBA levels, the association with T3 was significant, while that among the remainder was marginal. The association with T4 remained significant on sensitivity analysis, after controlling for other urinary chemicals.

CONCLUSION

Urinary 3-PBA levels in the general Korean adult population were found to be generally higher than those of other countries, and were associated with decreased TH levels. Considering the importance of THs, the public health implications of pyrethroid insecticide exposure warrant further studies.

Pyrethroid levels in toddlers' breathing zone following a simulated indoor pesticide spray

Application of pyrethroid insecticides in residential settings may result in children's exposures to these chemicals and possible adverse health effects. Household dust is a recognized reservoir for pyrethroids and a potential medium for multi-route pyrethroid exposure. Young children move and play in a manner that resuspends dust, and since their breathing zone is close to the floor, they will have higher inhalation exposure to pesticide-laden dust than other age groups. Directly measuring a toddler's exposure to household dust presents many logistic challenges. We simulated the dust resuspension induced by a toddler using a robot, which also served as a platform to collect air samples at the toddler's breathing zone height. We performed simulated pyrethroid residential spray and dust resuspension experiments on vinyl and carpeted floors. The mean pyrethroid airborne concentrations in the stationary and mobile samples were 0.065 μg/m³ and 0.143 μg/m³ for the vinyl floor with 1 g/m² dust loading, and 0.034 μg/m³ and 0.061 μg/m³ for the carpeted floor with 10 g/m² dust loading, respectively. Pyrethroids concentrations in the settled dust samples were significantly lower than that measured in the stationary and mobile samples in the carpeted floor experiments. Thus, the use of stationary samples and settled dust samples may underestimate a toddler's personal inhalation exposure to pyrethroids in residential houses.

Poisoning due to household products: A ten years retrospective analysis of telephone calls to the National Poisons Information Centre, All India Institute of Medical Sciences, New Delhi, India

Extensive use of different chemicals in various fields and their easy availability has led to an increased incidence of accidental and intentional poisoning in developing countries including India. A diverse range of household products commonly used for domestic purposes comprise pesticides, household cleaners, thermometer mercury, antiseptics, kerosene, paint thinners etc. Any of these products, if misused or mishandled can cause poisoning. In India, the National Poisons Centre (NPIC) at the All India Institute of Medical Sciences, New Delhi, provides information on management of poisoning to treating physicians. Analysis of data based on telephone calls received by the NPIC (April 2006-March 2016) has highlighted a high incidence of poisoning due to household products, followed by pharmaceuticals, agricultural pesticides and industrial chemicals. The objective of the present retrospective study was to determine the incidence of poisoning due to various household products as reported to the NPIC during the ten years period. The total number of calls received by the Centre was 16,420. There were 7114 calls (45.5%) due to household products with adults (>18yrs.) and children (<1-18yrs.) constituting 38.7% and 61.2% calls respectively. Males outnumbered females (M = 62.4%, F = 37.5%). The mode of poisoning was mainly unintentional (66.8%) followed by intentional mode (33.2%). The commonest route of exposure was oral (95.6%). Household pesticides were commonly implicated (43.7%) followed by household cleaners (21.8%), thermometer mercury (5.2%) naphthalene balls (5%), antiseptics (3%), kerosene (2%) and paint thinner (2%). Miscellaneous products comprising of camphor, silica gel, hair dye, nail polish remover, cosmetics, adhesives etc were also involved in poisoning (17.1%). The trend and pattern of poisoning varies in different parts of the country, because all calls on poisoning are not reported to the Centre. So the data as such may not be a true reflection of the scenario in India. However, the results do indicate an increasing incidence of poisoning due to household products especially in children. The probable reasons for high incidence could be careless storage, ignorance, non compliance with prescribed instructions for use and negligible parental supervision in case of children. The results of the study highlight, an urgent need to identify high risk circumstances, common toxic products involved and implementation of prevention and awareness programmes, to achieve poisons control at home.

Characteristics of acute occupational pesticide exposures reported to poison control centers in Texas, 2000-2015

In the United States, there is limited literature on occupational pesticide exposures despite being associated with adverse health outcomes, including in large states such as Texas. The purpose of this article is to characterize occupational pesticide poison center exposures in Texas. Descriptive statistics were used to describe exposures (eg, exposure routes, type of pesticide, medical outcome, clinical effects, and temporal/seasonal patterns). From 2000 to 2015, there were 2,303 occupational pesticide poison center exposures. Common types of reported pesticides were insecticides (67.3%), herbicides (17.7%), and repellents (5.8%). The highest proportion of exposures were among those aged 20 to 29 years (24.9%). The top clinical effect categories were gastrointestinal (25.8%), neurological (19.2%), and dermal (14.9%). Characterizing occupational pesticide poison center exposures can support improved surveillance systems and guide future research or interventions.

Acute Pesticide Poisoning in Children: Hospital Review in Selected Hospitals of Tanzania

BACKGROUND

Acute pesticide poisoning (APP) is a serious problem worldwide. Because the burden of childhood APP is unknown in Tanzania, this study describes the distribution, circumstances, and patterns of APP involving children under 18 years in Tanzania.

METHODOLOGY

A 12-month prospective study was conducted in 10 Tanzanian healthcare facilities in 2006 using a data collection tool for surveillance.

RESULTS

Of 53 childhood poisoning cases identified, 56.6% were female. The most common poisoning circumstances were accidents (49.1%) and suicide (30.2%). The most vulnerable children were 16-17 years old (30.2%). Suicide was significantly more common in females (PRR females/males = 1.66; 95% CI = 1.03-2.68) and accidental cases were more common in children aged 10 years or younger. Suicide was concentrated in children over 10 years, comprising 53% of cases in this age group. Organophosphates (OPs), zinc phosphide, and endosulfan were common amongst reported poisoning agents. The annual APP incidence rate was 1.61/100,000.

CONCLUSION

APP is common among children in this region of Tanzania. Prevention of suicide in older children should address mental health issues and control access to toxic pesticides. Prevention of accidents in younger children requires safer storage and hygiene measures. Diverse interventions are needed to reduce pesticide poisoning among children in Tanzania.

Pet Groomer's Lung: A novel occupation related hypersensitivity pneumonitis related to pyrethrin exposure in a pet groomer

A 61-year-old man was evaluated for a 2 month history of cough and dyspnea without relevant exposures other than pyrethrin containing insecticidal sprays he used while grooming dogs almost daily. High Resolution Computed Tomography (HRCT) of the chest demonstrated a Non-Specific Interstitial Pneumonia (NSIP) pattern. Pulmonary function testing revealed an isolated mildly reduced diffusion capacity. Bronchoalveolar lavage (BAL) results confirmed the presence of foamy histiocytes, lymphocytes, and polymorphonuclear cells consistent with ongoing exposure. Open lung biopsy showed poorly formed granulomas and bronchiolitis. He was advised to avoid exposure to pyrethrin. While he declined to stop grooming dogs, on follow-up, his symptoms had improved with use of a P100 mask and better ventilation to protect himself when using the pet sprays. We conclude that sustained exposure to pyrethrin containing sprays in the pet grooming industry may be a risk factor for a novel occupation related hypersensitivity pneumonitis. ("Pet Groomer's Lung"). Am. J. Ind. Med. 60:141-145, 2017. © 2016 Wiley Periodicals, Inc.

Climate conditions associated with the occurrence of pyrethroid residues in bulk milk tank

ABSTRACT The present study attempted to identify climate conditions that are associated with the occurrence of pyrethroid residues using a multivariate principal component analysis (PCA). A total of 132 raw milk samples were collected from dairy farms in Minas Gerais State - Brazil and analyzed for seven analytes using gas chromatography with electron capture detection. Of the 132 milk samples, pyrethroid residues were identified in 14 (10.6%) milk samples, of which 12 (9.1%) and two (1.5%) milk samples had the identification of cypermethrin and deltamethrin, respectively. From those samples, nine (6.8%) milk samples were regarded as non-compliant for cypermethrin with this analyte concentration above the maximum residue limits set by Brazilian legislation. A PCA assessing pyrethroid residues in bulk tank milk demonstrated that the average temperature and the Temperature-Humidity Index were associated with pyrethroids residues in bulk milk tank, although the relative humidity was inversely correlated. Thus, the data analysis indicated that the pyrethrid residues associated with some climate conditions can predict the moments with higher risk of occurrence of pyrethroid residues in bulk tank milk.

Home Use of a Pyrethroid-Containing Pesticide and Facial Paresthesia in a Toddler: A Case Report

Paresthesias have previously been reported among adults in occupational and non-occupational settings after dermal contact with pyrethroid insecticides. In this report, we describe a preverbal 13-month-old who presented to his primary care pediatrician with approximately 1 week of odd facial movements consistent with facial paresthesias. The symptoms coincided with a period of repeat indoor spraying at his home with a commercially available insecticide containing two active ingredients in the pyrethroid class. Consultation by the Northwest Pediatric Environmental Health Specialty Unit and follow-up by the Washington State Department of Health included urinary pyrethroid metabolite measurements during and after the symptomatic period, counseling on home clean up and use of safer pest control methods. The child's symptoms resolved soon after home cleanup. A diagnosis of pesticide-related illness due to pyrethroid exposure was made based on the opportunity for significant exposure (multiple applications in areas where the child spent time), supportive biomonitoring data, and the consistency and temporality of symptom findings (paresthesias). This case underscores the vulnerability of children to uptake pesticides, the role of the primary care provider in ascertaining an exposure history to recognize symptomatic illness, and the need for collaborative medical and public health efforts to reduce significant exposures in children.

Silicone wristbands detect individuals' pesticide exposures in West Africa

We detected between 2 and 10 pesticides per person with novel sampling devices worn by 35 participants who were actively engaged in farming in Diender, Senegal. Participants were recruited to wear silicone wristbands for each of two separate periods of up to 5 days. Pesticide exposure profiles were highly individualized with only limited associations with demographic data. Using a 63-pesticide dual-column gas chromatography-electron capture detector (GC-ECD) method, we detected pyrethoid insecticides most frequently, followed by organophosphate pesticides which have been linked to adverse health outcomes. This work provides the first report of individualized exposure profiles among smallholder farmers in West Africa, where logistical and practical constraints have prevented the use of more traditional approaches to exposure assessment in the past. The wristbands and associated analytical method enabled detection of a broad range of agricultural, domestic, legacy and current-use pesticides, including esfenvalerate, cypermethrin, lindane, DDT and chlorpyrifos. Participants reported the use of 13 pesticide active ingredients while wearing wristbands. All six of the pesticides that were both reportedly used and included in the analytical method were detected in at least one wristband. An additional 19 pesticide compounds were detected beyond those that were reported to be in use, highlighting the importance of measuring exposure in addition to collecting surveys and self-reported use records. The wristband method is a candidate for more widespread use in pesticide exposure and health monitoring, and in the development of evidence-based policies for human health protection in an area where food security concerns are likely to intensify agricultural production and pesticide use in the near future.

Assessment of genotoxicity of pyrethrin in cultured human lymphocytes

Pyrethrin is an insecticide that is obtained from the Chrysanthemum flower (Pyrethrum). In this study, we examined the genotoxic effects of pyrethrin on cultured human lymphocytes using sister chromatid exchanges (SCEs) and 8-hydroxy deoxyguanosine (8-OHdG) assays. Cultures were treated with different concentrations of pyrethrin (25, 50, and 100 μg/mL), which was dissolved in in dimethyl sulfoxide (DMSO). The results showed that treatment of cultured lymphocytes with pyrethrin at 50 μg/mL and 100 μg/mL induced significant elevation in SCEs (p < 0.05). In addition, the 100 μg/mL concentration significantly affected both mitotic and proliferative indices (p < 0.05). Finally, pyrethrin induced significant elevation in the oxidative stress marker 8-OHdG in a dose-dependent manner (p < 0.001). In conclusion, the results suggest that pyrethrin is genotoxic as measured by two independent assays on genetic toxicity.

[Acute poisoning by pesticides in children]

Acute pesticide poisoning in children is rare but potentially serious. Some clinical patterns (toxidromes) are suggestive of the drug class: cholinergic crisis for organophosphate or carbamate insecticides; neurological syndrome for rodenticides; digestive and respiratory syndrome for herbicides. Treatment is symptomatic and only a few patients are treated with an antidote: atropine and pralidoxime for organophosphate insecticides, vitamin K for anticoagulant rodenticides.

Developing and applying the adverse outcome pathway concept for understanding and predicting neurotoxicity

The Adverse Outcome Pathway (AOP) concept has recently been proposed to support a paradigm shift in regulatory toxicology testing and risk assessment. This concept is similar to the Mode of Action (MOA), in that it describes a sequence of measurable key events triggered by a molecular initiating event in which a stressor interacts with a biological target. The resulting cascade of key events includes molecular, cellular, structural and functional changes in biological systems, resulting in a measurable adverse outcome. Thereby, an AOP ideally provides information relevant to chemical structure-activity relationships as a basis for predicting effects of structurally similar compounds. AOPs could potentially also form the basis for qualitative and quantitative predictive modeling of the human adverse outcome resulting from molecular initiating or other key events for which higher-throughput testing methods are available or can be developed. A variety of cellular and molecular processes are known to be critical for normal function of the central (CNS) and peripheral nervous systems (PNS). Because of the biological and functional complexity of the CNS and PNS, it has been challenging to establish causative links and quantitative relationships between key events that comprise the pathways leading from chemical exposure to an adverse outcome in the nervous system. Following introduction of the principles of MOA and AOPs, examples of potential or putative adverse outcome pathways specific for developmental or adult neurotoxicity are summarized and aspects of their assessment considered. Their possible application in developing mechanistically informed Integrated Approaches to Testing and Assessment (IATA) is also discussed.

The neurotoxicity of organochlorine and pyrethroid pesticides

Organochlorine and pyrethroid compounds represent an old and a new class, respectively, of insecticides. Organochlorines such as DDT, dieldrin, or chlordecone, have been banned, primarily because of environmental issues. DDT is still used in certain countries to fight malaria-bearing mosquitoes, while lindane still finds some limited used against head lice. In contrast, pyrethroids find widespread use because of their efficacy, low environmental persistence, and relatively low mammalian toxicity. Like all insecticides, organochlorines and pyrethroids target the nervous system of insects and of nontarget species. All pyrethroids and DDT interact with the sodium channel; by keeping it open longer, they increase the likelihood of action potentials developing, thus creating a condition of hyperexcitability, whose main clinical sign is tremors. Most other organochlorines (except chlordecone), as well as certain (type II) pyrethroids, block the chloride channels of the GABA-A receptor, and cause seizures. Evidence of an association between exposure to organochlorine and pyrethroid insecticides and neurodegenerative diseases (e.g., Parkinson's disease) is weak, at best.