Organochlorine pesticides levels and associated factors in a group of blood donors in São Paulo, Brazil

Measurement of pesticides in hair samples from pemphigus foliaceus and pemphigus vulgaris patients in Southeastern Brazil

BACKGROUND

Pesticides, mainly organophosphates (OP), have been related to increased risk of pemphigus vulgaris (PV) and pemphigus foliaceus (PF), nevertheless, their measurement has not been determined in pemphigus patients.

OBJECTIVE

To evaluate pesticide exposure and pesticide measurement, comparing PV, PF and control groups in Southeastern Brazil.

METHODS

Information about urban or rural residency and exposure to pesticides at the onset of pemphigus was assessed by questionnaire interview; hair samples from the scalp of PV, PF, and controls were tested for OP and organochlorines (OC) by gas-phase chromatography coupled to mass spectrometry.

RESULTS

The minority of PV (2 [7.1%] of 28) and PF (7 [18%] of 39), but none of the 48 controls, informed living in rural areas at the onset of pemphigus (p = 0.2853). PV (33.3%), PF (38.5%), and controls (20%) informed exposure to pesticides (p = 0.186). Twenty-one (14.8%) of 142 individuals tested positive for OP and/or OC: PV (2 [6.3%] of 32) and PF (11 [25.6%] of 43) had similar pesticides contamination as controls (8 [11.9%] of 67) (p = 0.4928; p = 0.0753, respectively), but PF presented higher contamination than PV (p = 0.034). PV did not present any positivity for OP. Three (7%) PF tested positive for both OP and OC. Some PF tested positive for three or four OP, mainly diazinon and dichlorvos.

STUDY LIMITATION

Lack of data for some controls.

CONCLUSION

Although the frequency of PV and PF patients exposed to pesticides was similar, pesticides were more frequently detected in hair samples from PF compared to PV. The cause-effect relationship still needs to be determined.

Spatiotemporal evaluation of organochlorine pesticide residues in bottom sediments of the Rio de Ondas hydrographic basin, western Bahia, Brazil

The Rio de Ondas Hydrographic Basin (ROHB), Bahia state, Brazil, is located in a region with abundant water resources and is highly impacted by intense agricultural activity. In such a scenario, the use of organochlorine pesticides can represent a potential risk to the aquatic environments, due to their persistence, high bioaccumulation capacity, and high toxicity. Thus, organochlorine pesticide residues in bottom sediment samples from rivers on eighteen sites distributed along the ROHB in the dry and rainy periods were analyzed by gas chromatography coupled with mass spectrometry. The validated method showed no matrix effect, recoveries ranging from 82% (β-HCB) to 118% (DDD), limits of detection between 0.003 ng g^-1 (α-HCH) and 0.011 ng g^-1 (DDT), limits of quantification of 0.010 ng g^-1 (α-HCH) to 0.036 ng g^-1 (DDT), repeatability with the highest relative standard deviation of 0.97% (α-hexachlorocyclohexane at 2.000 ng g^-1), and inter-day precision ranging from 10% (aldrin at 0.050 ng g^-1 and 0.600 ng g^-1 and α-endosulfan at 0.600 ng g^-1) to 25% (β-endosulfan at 0.050 ng g^-1). Although most compounds were banned since 1985, it was observed that their residues were widely distributed in the ROHB, with the total concentrations varying from 3.242 ng g^-1 (P02) to 12.052 ng g^-1 (P17) and from 0.313 ng g^-1 (P14) to 30.861 ng g^-1 (P13) in the dry and rainy periods, respectively, which may be related to historical contamination and/or prohibited use. Moreover, the spatiotemporal variation showed the highest concentrations of organochlorine pesticide residues in the rainy season, coinciding with the planting period.

The Influence of Synthesis Methods and Experimental Conditions on the Photocatalytic Properties of SnO2: A Review

Semiconductors based on transition metal oxides represent an important class of materials used in emerging technologies. For this, the performance of these materials strongly depends on the size and morphology of particles, surface charge characteristics, and the presence of bulk and surface defects that are influenced by the synthesis method and the experimental conditions the materials are prepared. In this context, the present review aims to report the importance of choosing the synthesis methods and experimental conditions to modify structural, morphological, and electronic characteristics of semiconductors, more specifically, tin oxide (SnO2), since these parameters may be a determinant for better performance in various applications, including photocatalysis. SnO2 is an n-type semiconductor with a band gap between 3.6 and 4.0 eV, whose intrinsic characteristics are responsible for its electrical conductivity, good optical characteristics, high thermal stability, and other qualities. Such characteristics have provided excellent results in advanced oxidative processes, i.e., heterogeneous photocatalysis applications. This process involves semiconductors in the production of hydroxyl radicals via activation by light absorption, and it is considered as an emerging and promising technology for domestic-industrial wastewater treatment. In our review article, we focused on the photodegradation of different organic dyes and types of persistent organic pollutants using SnO2-based photocatalysts, and how the efficiency of these materials can be impacted by synthesis methods and experimental conditions employed to prepare them.

Differential Bioaccumulation Patterns of α, β-Hexachlorobenzene and Dicofol in Adipose Tissue from the GraMo Cohort (Southern Spain)

To identify bioaccumulation patterns of α-, β- hexachlorocyclohexane (HCH) and dicofol in relation to sociodemographic, dietary, and lifestyle factors, adipose tissue samples of 387 subjects from GraMo cohort in Southern Spain were analyzed. Potential predictors of these organochlorine pesticides (OCP) levels were collected by face-to-face interviews and assessed by multivariable linear and logistic regression. OCPs were detected in 84.2% (β-HCH), 21.7% (α-HCH), and 19.6% (dicofol) of the population. β-HCH levels were positively related to age, body mass index (BMI), mother's occupation in agriculture during pregnancy, living in Poniente and Alpujarras, white fish, milk and water consumption, and negatively related to being male, living near to an agricultural area, working ≥10 years in agriculture, and beer consumption. Detectable α-HCH levels were positively related to age, BMI, milk consumption, mother's occupation in agriculture during pregnancy, and negatively with residence in Poniente and Alpujarras, Granada city, and Granada Metropolitan Area. Residence near to an agricultural area, smoking habit, white fish and water consumption, and living in Poniente and Alpujarras, Granada city and Granada Metropolitan Area were negatively associated with detectable dicofol levels. Our study revealed different bioaccumulation patterns of α, β-HCH and dicofol, probably due to their dissimilar period of use, and emphasize the need for assessing the exposure to frequently overlooked pollutants.

Impact of Pesticides on Human Health in the Last Six Years in Brazil

Every year, Brazil intensifies its activity in agriculture and, as a result, it has become one of the biggest consumers of pesticides in the world. The high rate of these substances raises environmental and human health concerns. Therefore, we collected papers from PubMed, Scopus, Scielo, and Web of Science databases, from 2015 to 2021. After a blind selection using the software Rayyan QCRI by two authors, 51 studies were included. Researchers from the South and the Southeast Brazilian regions contributed to most publications, from areas that concentrate agricultural commodity complexes. Among the pesticides described in the studies, insecticides, herbicides, and fungicides were the most frequent. The articles reported multiple toxic effects, particularly in rural workers. The results obtained can be used to direct policies to reduce the use of pesticides, and to protect the health of the population.

Quercetin protects human liver cells from o,p'-DDT-induced toxicity by suppressing Nrf2 and NADPH oxidase-regulated ROS production

Epidemiologic studies have revealed that Dichlorodiphenyltrichloroethane (DDT) and its metabolites are associated with liver diseases. However, there has been little emphasis on the mechanism underlying liver toxicity of o,p'-DDT and relevant effective inhibitors investigation. This study indicated o,p'-DDT exposure significantly decreased cell viability and promoted lactate dehydrogenase (LDH) release based on the investigation of cytotoxicity by trypan blue exclusion counts, MTT, and lactate dehydrogenase (LDH) assays. Comet, micronuclei, and DNA-protein crosslinks (DPC) assays demonstrated o,p'-DDT exposure increased the comet parameters, micronuclei frequency, and DPC coefficient. Meanwhile, we found o,p'-DDT induced mitochondria-dependent apoptosis, which is characterized by the loss of of mitochondrial membrane potential (Δψm), decreased Bcl-2 expression, and increased protein levels of Bax, cytochrome c, activated-caspase-9, and activated-caspase-3. Furthermore, o,p'-DDT induced reactive oxygen species (ROS) overproduction, decreased the protein levels of nuclear factor erythroid-derived 2-like 2 (Nrf2) in the nuclear, and enhanced the expression of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase. However, quercetin treatment significantly antagonized o,p'-DDT-induced cytotoxicity, genotoxicity, and apoptosis as well as effects on ROS, Nrf2, and NADPH oxidase. Taken together, these findings suggested quercetin could alleviate o,p'-DDT-induced toxicity in HL-7702 cells via inhibiting ROS production, which is modulated by down-regulating nuclear Nrf2 levels and NADPH oxidase expression.

1,1,1-trichloro-2,2-bis (p-chlorophenyl)-ethane (DDT) and 1,1-Dichloro-2,2-bis (p, p'-chlorophenyl) ethylene (DDE) as endocrine disruptors in human and wildlife: A possible implication of mitochondria

1,1,1-trichloro-2,2-bis (p-chlorophenyl)-ethane (DDT) and its main metabolite 1,1-Dichloro-2,2-bis (p, p'-chlorophenyl) ethylene (DDE) act as endocrine disruptors in humans and wildlife. Immunomodulatory functions have also been attributed to both xenobiotics. DDT was banned in the 1970s due to its toxicity, but it is still produced and used for indoor residual spraying with disease vector control purposes. Due to their persistence and lipophilic properties, DDT and DDE can bioaccumulate through the food chain, being stored in organisms' adipose depots. Their endocrine disruptor function is mediated by agonist or antagonist interaction with nuclear receptors. Present review aimed to provide an overview of how DDT and DDE exposure impacts reproductive and immune systems with estrogen-disrupting action in humans and wildlife. Studies showing DDT and DDE impact on mitochondrial function and apoptosis pathway will also be reviewed, suggesting the hypothesis of direct action on mitochondrial steroid receptors.

Evaluating the Level of Pesticides in the Blood of Small-Scale Farmers and Its Associated Risk Factors in Western Ethiopia

BACKGROUND

The presence of agricultural pesticide residue can cause adverse health effects.The main objective of this study was to evaluate the level of pesticides in the blood of small-scale farmers (SSFs) and associated risk factors in western Ethiopia.

METHODS

Across sectional study was conducted in June 2020 using 240 blood samples, 140 from the exposed small-scale farmers (ESSFs) and 100 from non-exposed small-scale farmers (NESSFs). The blood sample analysis was mad for 5 organochlorines (OCs) and 3 synthetic pyrethroids (SPs) pesticides by gas-liquid chromatography with an electron capture detector (GC-ECD) methods. Extraction, and clean up of the samples were made by using standard analytical methods. To define the relationships between the outcomes and explanatory variables, logistic regression models were used.

RESULTS

The results shows that p,p'-DDT, heptachlor and deltamethrin were the most frequently detected pesticides with 96.4%, 95%, and 100% in both ESSFs and NESSFs, respectively. The ESSFs blood samples have shown the highest mean concentrations of permethrin and p,p'-DDT(1.26 ± 0.15) and (0.28 ± 0.4) mgL^-1, respectively. SSFs under the age of 40 were 21% less likely to be exposed to permethrin than those above the age of 40 (Adjusted Odd Ratio, AOR, 0.21; 95% CI: 0.1-0.44). Male SSFs were 17 times more likely to be exposed to heptachlor than females (AOR, 17.36; 95%CI: 7.34-41.09) and farmers with no formal education were 18 times more likely to be exposed to deltamethrin than those with primary schools and beyond (AOR, 18.1; 95 %CI: 4.53-72.06). Furthermore, SSFs that did not use PPE appropriately were 3.6 and 6.21 times more likely to be exposed to cypermethrin (AOR, 3.6; 95%CI: 1.94-6.54) and p,p'-DDE(AOR, 6.21; 95%CI: 3.38-11.41) blood levels than those who did, respectively. SSFs that perform different activities like eating and drinking (11%), chewing (10%), and diverse activities (8%) were more likely to be exposed to p,p'-DDT than those farmers who didn't use pesticides.

CONCLUSIONS

This study identified a high concentration p,p'-DDE, p,p'-DDT, heptachlor, cypermethrin, permethrin, and deltamethrin in the blood of small scale farmers. The older age, less education, and farmers with inappropriate PPE use are more likely exposed to pesticides.

Determination of DDT in honey samples by liquid-liquid extraction with low-temperature purification (LLE-LTP) combined to HPLC-DAD

Honey is widely consumed worldwide, however, this food can be contaminated by chemical contaminants, such as the insecticide dichlorodiphenyltrichloroethane (DDT). Despite legal restrictions on DDT use, this organochlorine pesticide has been detected in honey collected in several developed and developing countries, representing risks to human health, animals, and the environment due to its high environmental persistence, potential carcinogenicity, and ecotoxicological effects. Thus, the development of an analytical method for DDT monitoring in this matrix is important to ensure food security. Therefore, this study aimed to optimize and validate a simple, low-cost, and efficient method using the liquid-liquid extraction with low-temperature purification (LLE-LTP) to determine DDT in honey samples by high-performance liquid chromatography with diode array detector (HPLC-DAD). The proposed method was validated according to SANTE guidelines, being considered selective, precise, accurate, and linear in the range of 8.0-160 μg kg^-1. The limits of detection (LOD) and quantification (LOQ) achieved were 4.0 and 8.0 μg kg^-1, respectively. This LOQ value is lower than the maximum residue limit established by the Brazilian and European Union legislation. Therefore, the LLE-LTP combined to HPLC-DAD allows the routine analysis of DDT in honey samples and can be widely applied in studies to monitor this pesticide, especially in developing countries, where DDT use is still allowed.

Agrotóxicos e seus impactos na saúde humana e ambiental: uma revisão sistemática

RESUMO Atualmente, o Brasil é o maior consumidor de agrotóxicos do mundo. Diversos estudos comprovam os malefícios para a saúde humana e ambiental da exposição aos agrotóxicos. Realizou-se uma revisão sistemática no período de 2011 a 2017 acerca desse tema em bases de dados científicos. Foram incluídos 116 estudos que demonstraram o impacto negativo para a saúde humana e ambiental. É essencial a realização de estudos sobre os efeitos da exposição crônica e simultânea a diversos agrotóxicos, além de estudos sobre os nexos de determinação estrutural do uso dos venenos e suas consequências.