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Results: The present study compared three scabicidal agents alone or with combination, the currently considered medicine of choice permethrin, oral ivermectin, and gamma benzene hexachloride in the local population of India. A total of 120 patients were studied. They were randomly divided into four groups -Group A, Group B, Group C, and Group D. Group A received topical 5% permethrin and oral placebo. Group B was given topical placebo cream and oral ivermectin in two dose regimen. Group C received topical 1% gamma benzene hexachloride with oral placebo, and Group D was given topical 5% permethrin and oral ivermectin. The improvement of lesions and pruritus were assessed in the next three follow-ups, i.e., on the 7th day, 14th day, and 28th day along with any adverse drug reactions (ADRs). It was found that Group A had 83%, 90%, 97%, and Group B had 70%, 81%, and 91% improvement of lesions in the three follow-ups respectively. Group C showed 57%, 70%, 86%, and Group D had 82%, 90%, 97% efficiency to decrease lesion count (p>0.05) respectively. Again, Group A observed 77%, 88%, and 94% improvement in pruritus in subsequent follow-ups, while for Group B it was 63%, 76%, and 86%. Group C had 55%, 71%, 85% efficiency, and Group D had recorded 77%, 88%, and 94% improvement to decrease pruritus (p>0.05). The incidence of adverse effects was found to be less in Group B, Group C, and Group D when compared to Group A., Conclusion: Group D or a combination therapy was a better choice for scabies in comparison to other monotherapy due to its better efficacy and safety profile., Competing Interests: None

This study investigates acute toxicity and histological effects of Lindane insecticide on intestinal tissues of immature grass carp (Ctenopharyngodon idella). For these purposes, 105 fish were exposed to different concentrations of Lindane for 96 h in 5 groups with 3 replications. Samples of intestinal tissues were prepared in both control and exposure groups during and after the toxicity test. Vaculation, necrosis, bleeding and epithelial degeneration were apparent in the intestine tissue of treated individuals. The LC 50 96 h of Lindane was 0.788 ppm in the present study, also the results showed besides pesticide-induced lesions, symptoms of abnormal swimming, anxiety, tendency to swim near the surface, and death due to terminal toxicity with mouth widely open. The exposed fish were pale in color, showed oxygen deficit and severe respiratory problems. Overall, our results confirm the toxicity of different concentrations of Lindane insecticide affecting behavior, intestinal function and inducing tissue lesions of immature grass carp., (© 2021. The Author(s), under exclusive licence to Springer Nature B.V.)

Organochlorine pesticides constitute the majority of the total environmental pollutants, and a wide range of compounds have been found to be carcinogenic to humans. Among all, growing interest has been focused on β-hexachlorocyclohexane (β-HCH), virtually the most hazardous and, at the same time, the most poorly investigated member of the hexachlorocyclohexane family. Considering the multifaceted biochemical activities of β-HCH, already established in our previous studies, the aim of this work is to assess whether β-HCH could also trigger cellular malignant transformation toward cancer development. For this purpose, experiments were performed on the human normal bronchial epithelium cell line BEAS-2B exposed to 10 µM β-HCH. The obtained results strongly support the carcinogenic potential of β-HCH, which is achieved through both non-genotoxic (activation of oncogenic signaling pathways and proliferative activity) and indirect genotoxic (ROS production and DNA damage) mechanisms that significantly affect cellular macroscopic characteristics and functions such as cell morphology, cell cycle profile, and apoptosis. Taking all these elements into account, the presented study provides important elements to further characterize β-HCH, which appears to be a full-fledged carcinogenic agent.

Insecticide use has been linked to increased risk of non-Hodgkin lymphoma (NHL), however, findings of epidemiologic studies have been inconsistent, particularly for NHL subtypes. We analyzed 1690 NHL cases and 5131 controls in the North American Pooled Project (NAPP) to investigate self-reported insecticide use and risk of NHL overall and by subtypes: follicular lymphoma (FL), diffuse large B-cell lymphoma (DLBCL) and small lymphocytic lymphoma (SLL). Odds ratios (OR) and 95% confidence intervals for each insecticide were estimated using logistic regression. Subtype-specific associations were evaluated using ASSET (Association analysis for SubSETs). Increased risks of multiple NHL subtypes were observed for lindane (OR = 1.60, 1.20-2.10: FL, DLCBL, SLL), chlordane (OR = 1.59, 1.17-2.16: FL, SLL) and DDT (OR = 1.36, 1.06-1.73: DLBCL, SLL). Positive trends were observed, within the subsets with identified associations, for increasing categories of exposure duration for lindane (P trend = 1.7 × 10 -4 ), chlordane (P trend = 1.0 × 10 -3 ) and DDT (P trend = 4.2 × 10 -3 ), however, the exposure-response relationship was nonlinear. Ever use of pyrethrum was associated with an increased risk of FL (OR = 3.65, 1.45-9.15), and the relationship with duration of use appeared monotonic (OR for >10 years: OR = 5.38, 1.75-16.53; P trend = 3.6 × 10 -3 ). Our analysis identified several novel associations between insecticide use and specific NHL subtypes, suggesting possible etiologic heterogeneity in the context of pesticide exposure., (© 2020 The Authors. International Journal of Cancer published by John Wiley & Sons Ltd on behalf of Union for International Cancer Control.)

Background: T-cell immunosenescence, a hallmark of an aging immune system, is potentially linked to the risk of developing cancer and other aging-related diseases. Chronic infection by cytomegalovirus (CMV) has been widely studied as a risk factor for T-cell immunosenescence, but the role of persistent chemicals has never been examined. As a typical example of persistent chemicals, we evaluated whether organochlorine pesticides (OCPs) are related to T-cell immunosenescence in the general population. Methods: Serum concentrations of β-hexachlorocyclohexane, p,p '-DDT, p,p '-DDE, and trans-nonachlor were measured in 95 Korean adults ages 30 to 64 years. T-cell immunosenescence was assessed by the frequencies of CD8 + CD57 + , CD8 + CD28 - , CD4 + CD57 + , and CD4 + CD28 - T lymphocytes in 20 mL of fresh peripheral blood. Results: The senescence of CD8 + T lymphocytes was the most consistently associated with OCPs. For quartiles of measurements of OCPs, adjusted mean percentages of CD8 + CD57 + and CD8 + CD28 - T lymphocytes in the CD8 + T lymphocyte population were 23.9, 27.6, 31.0, and 38.7 ( P trend < 0.01) and 25.6, 27.3, 28.0, and 35.5 ( P trend = 0.02), respectively. When we compared the strength of the associations among OCPs, CMV IgG titer, and age, OCPs showed the strongest association with markers of immunosenescence. Importantly, the association between OCPs and immunosenescence markers was more prominent among participants without known risk factors, such as a young age or low CMV immunoglobulin G titer. Conclusions: Chronic exposure to low-dose OCPs may be a new risk factor for T-cell immunosenescence. Impact: T-cell immunosenescence may be one possible mechanism linking low-dose OCPs and many chronic diseases. Cancer Epidemiol Biomarkers Prev; 27(10); 1159-67. ©2018 AACR ., (©2018 American Association for Cancer Research.)

Dried blood spots (DBS) on filter paper provide a simple and convenient means of collecting, storing and shipping samples for veterinary diagnostics related to toxin exposures. This paper presents validation data on analysis of DBS for chlorinated persistent organic pollutants, specifically 4,4'-dichloro-diphenyl-trichloroethane (4,4'-DDT) and its breakdown product 4,4'-dichlorodiphenyl-dichloroethylene (4,4'-DDE), lindane and a representative polychlorinated biphenyl (PCB) congener PCB-153. Analysis was by gas chromatography with electron capture detection (GC-ECD). The method required one 12.5 mm diameter spot representing application of 50 μL of blood, and working limits of detection (LOD) for each of the compounds was 5 ppb. Data are presented on development and description of the method, assay precision, LOD and quantitation, linearity, accuracy, specificity, effects of long-term storage and ruggedness. The method was also applied to 27 avian DBS, and 4,4'-DDE was detected in the majority of samples.

Growing evidence links environmental exposure to hexachlorocyclohexanes (HCHs) to the risk of type 2 diabetes mellitus (T2DM), and ADIPOQ that encodes adiponectin is considered as an important gene for T2DM. However, the role of ADIPOQ-HCH interaction on T2DM risk remains unclear. Thus, a paired case-control study was conducted in an East Chinese community. A total of 1446 subjects, including 723 cases and 723 controls matched on age, gender and residence, were enrolled, and 4 types of HCH isomers were measured in serum samples using GC-MS/MS. Additionally, 4 candidate ADIPOQ SNPs (rs182052, rs266729, rs6810075, and rs16861194) were genotyped by TaqMan assay, and plasma adiponectin was measured using ELISA. No associations between 4 SNPs and T2DM risk were found, but T2DM risk significantly increased with serum levels of β-HCH (P < 0.001). Furthermore, the synergistic interaction between β-HCH and rs182052 significantly increased T2DM risk (OR I-additive model  = 2.20, OR I-recessive model  = 2.13). Additionally, individuals carrying only rs182052 (A allele) with high levels of β-HCH had significant reduction in adiponectin levels (P = 0.016). These results indicate that the interaction between rs182052 and β-HCH might increase the risk of T2DM by jointly decreasing the adiponectin level and potentially trigger T2DM development.

Scabies, whose etiologic agent is Sarcoptes scabiei, is a neglected parasitic disease that is a major public health problem in many resourcepoor regions. Its current therapies include benzyl benzoate, lindane, permethrin, sulfur, crotamiton, monosulfiram, and oral ivermectin. The aim of this study was to compare the efficacy and safety of lindane 1% lotion vs permethrin 5% in the treatment of scabies. A total of 120 patients with scabies attending a dermatology outpatient department were included. Patients were randomly divided into two groups. Sixty patients and their family contacts received 5% permethrin cream and the other 60 received 1% lindane lotion. Treatment was evaluated at intervals of 2 and 4 weeks. Permethrin provided improvement in 48 patients (80%) after 2 weeks, whereas lindane was effective in only 28 patients (46.6%). Permethrin (5%) cream was found to be significantly more effective in the treatment of scabies compared with lindane in this study. Adverse effects were rare in both the permethrin and lindane groups.

Background: This is the first study investigating scabies treatment since 1992 to involve examination of patients with microscopically confirmed scabies., Aim: To assess the efficacy of 1% lindane cream in treating microscopically confirmed scabies, and to determine the utility of dermoscopy-guided skin scraping with microscopic examination (DSGSS-ME) in evaluating the efficacy of scabies treatment., Methods: This retrospective study analysed patients treated for scabies between January 2012 and December 2013. From the hospital database, 287 cases of scabies were identified and 50 were enrolled in the study. Patients were treated with 1% lindane cream twice weekly (days 0 and 1) and were evaluated with DSGSS-ME on day 7. Treatment and evaluations were repeated once weekly until a negative DSGSS-ME result was obtained., Results: The cumulative efficacy of lindane 1% cream was 40% (20/50) after 1 week, 88% (44/50) after 2 weeks and 98% (49/50) after 3 weeks of treatment. There was a statistically significant difference between the 1- and 2-week (P = 0.03), and 1- and 3-week (P = 0.02) treatments. A total of 90 post-treatment DSGSS-MEs were performed, with a sensitivity of 97.3% (95% CI 85.8-99.9) and a negative predictive value of 98.2% (95% CI 90.1-100). Specificity and positive predictive value were 100%, as this procedure cannot yield false-positive results, because it relies on finding mites, eggs or faeces., Conclusions: We suggest that a twice-weekly schedule (on consecutive days) of 1% lindane treatment lasting at least 2 weeks is required to clear scabies. DSGSS-ME appears to be a good method to evaluate the efficacy of scabies treatment. This study introduces a safe and effective method to treat scabies, and to accurately monitor infestation status in patients., (© 2015 British Association of Dermatologists.)

Objectives: The cytochrome P-450c17α enzyme encoded by the cytochrome P-450c17α (CYP17A1) gene plays a role in oestrogen synthesis. Genetic variation in the maternal CYP17A1 gene leads to differences in oestrogen level that affect fetal growth and cause small for gestational age (SGA). Organochlorine pesticides (OCPs) are endocrine disruptors that alter the normal oestrogen-progesterone balance, and are associated with adverse reproductive outcomes. This study was designed to investigate the effect of the gene-environment interaction between maternal CYP17A1 gene polymorphisms and maternal and cord OCP levels on the risk of SGA., Study Design: Maternal and cord blood samples of 50 term SGA cases (birth weight <10th percentile for gestational age as per Lubchenco's growth chart) and 50 normal pregnancies (controls) were collected. Women with occupational exposure to OCPs, anaemia, hypertension, antiphospholipid antibody syndrome, medical disease, parity of more than four, or a history of smoking, alcohol consumption or chronic drug intake were excluded from both groups. Maternal and cord blood samples were collected at the time of delivery or after delivery, respectively. The OCP levels of the samples were analyzed using a gas chromatography system equipped with an electron capture detector, and polymerase chain reaction-restriction fragment length polymorphism was used for polymorphic analysis of the CYP17A1 gene., Results: Significantly (p<0.05) higher levels of α-hexachlorocyclohexane (HCH), β-HCH and γ-HCH were found in maternal and cord blood samples of the SGA cases compared with the controls. The frequency of the A1A2/A2A2 genotype was significantly lower [p=0.041, odds ratio (OR) 0.421, 95% confidence interval (CI) 0.184-0.966] in the SGA cases compared with the controls. When gene-environment interactions between CYP17A1 gene polymorphisms and OCP levels were considered, a significant (p=0.004) association was found between a high level of endosulfan in cord blood and the A1A1 (wild-type) genotype of CYP17A1, leading to an estimated reduction in birth weight of 315g., Conclusions: Higher OCP levels and the A1A1 genotype of CYP17A1 in pregnant women may be considered as important aetiological factors in idiopathic SGA. This study provides evidence that genetic variation and its interaction with environmental exposure may increase the risk of SGA. Further studies are needed with a larger sample size, incorporating other gene polymorphisms and environmental exposures, to strengthen these observations., (Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.)

Pediculosis (capitis, corporis, and pubis) share well-known features: worldwide prevalence (involving millions of people annually); parasites inducing skin lesions directly, and indirectly as a result of itching and hypersensitivity to parasites; and treatment based on good entomological knowledge of the parasite and practical considerations (ie, most available treatments do not act on eggs and should be repeated, depending on the life cycle of the parasites). Infestations are spread most commonly by close contacts. Social stigma and persistent misconceptions complicate the implementation of appropriate management strategies. Head and pubic lice infestations are diagnosed by the visualization of insects or viable nits (eggs). Primary treatments are topical pediculicides (permethrin or malathion), used twice, but emergence of resistance against pediculicides has created the need of alternative treatments including topical or oral ivermectin. Pubic lice are treated the same as head lice, but this finding should prompt evaluation for other sexually transmitted diseases. Body lice infestation should be suspected when symptoms of generalized itching occur in persons who do not change or wash their clothing or bedding regularly; lice may be found in the seams of their clothing.Topically administered permethrin may help to eradicate body lice, but personal hygiene measures are essential for successful treatment. Environmental treatment is also necessary for the eradication of the infestation. Health care personnel who come into contact with this population need to be well informed of the facts in order to disseminate accurate information for diagnosis and management.

Rapid economic growth in South China (including Guangdong Province, Hong Kong, and Macau), particularly within the Pearl River Delta region, has resulted in severe pollution of the natural eco-environment in the last three decades. Large amounts of monitoring data on organic pollution in the Pearl River Delta have been accumulated, which allows us to conduct a fairly comprehensive assessment of the state of the Pearl River Delta and elucidate spatial and temporal patterns of pollution on a regional scale. Of various causes for environmental deterioration, negative impact from persistent organic pollutants (POPs) is a global concern. This review examines the current levels and distribution patterns of several POPs, namely DDT (and its metabolites DDD and DDE), hexachlorocyclohexanes, and polybrominated diphenyl ethers, in various environmental compartments of South China. The general information on environmental occurrence, regional behaviors, ecological effects, and human exposure of these POPs in this region are reviewed., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Objectives: The aim was to examine the gene environment (GxE) interaction with reference to APO E genotypes, serum lipids and organochlorine pesticides (OCPs) as one of the factors in the etiology of Alzheimer's disease (AD)., Methods: A case control study was used to examine, APOE HhaI polymorphism by polymerase chain reaction (PCR)/PCRrestriction fragment length polymorphism method, serum lipids by autoanalyser and OCPs by gas chromatography (GC)., Results: APOE ∈4 allele frequency was significantly high (p=0.000, OR=5.73, CI=2.68-12.50) in AD as compared to controls. The serum cholesterol, β- hexachlorocyclohexane and dieldrin are risk factors for AD independent of the APOE ∈4 risk allele, recording an odds ratio of 1.16, 11.38 and 10.45 respectively., Conclusion: GxE interactions exist with APOE ∈4 allele status that need to be considered for the study design and analysis of such data in future studies of AD.

Insecticide treatment resistance is considered to be a major factor in the increasing number of infestations by head lice. The large insecticide selection pressure induced by conventional topical pediculicides has led to the emergence and spread of resistance in many parts of the world. Possible mechanisms of resistance include accelerated detoxification of insecticides by enzyme-mediated reduction, esterification, oxidation that may be overcome by synergistic agents such as piperonyl butoxide, alteration of the binding site, e.g. altered acetylcholinesterase or altered nerve voltage-gated sodium channel, and knockdown resistance (kdr). Clinical, parasitological and molecular data on resistance to conventional topical pediculicides show that treatments with neurotoxic insecticides have suffered considerable loss of activity worldwide. In particular, resistance to synthetic pyrethroids has become prominent, probably because of their extensive use. As other treatment options, including non-insecticidal pediculicides such as dimeticone, are now available, the use of older insecticides, such as lindane and carbaryl, should be minimized, owing to their loss of efficacy and safety concerns. The organophosphorus insecticide malathion remains effective, except in the UK, mostly in formulations that include terpineol., (© 2012 The Authors. Clinical Microbiology and Infection © 2012 European Society of Clinical Microbiology and Infectious Diseases.)

Objectives: Organochlorine pesticides (OCPs) and oxidative stress are reported to be associated with adverse reproductive outcomes. Glutathione S-transferase (GST) is a polymorphic supergene family involved in the detoxification of numerous toxins including OCPs. OCPs are endocrine disrupter and prenatal exposure to them may be associated with fetal growth restriction (FGR). The objectives of the present study were (i) to determine the frequencies of polymorphic alleles of GSTM1 and GSTT1 genes in women with idiopathic FGR, (ii) to analyze the maternal and cord blood levels of the OCPs, and (iii) to identify the gene environment interaction that increases the risk of FGR., Study Design: Maternal and cord blood samples of 50 FGR cases (birth weight <10 percentile for gestational age as per Lubchenco's growth chart) and equal number of normal pregnancies who were occupationally non exposed to OCPs and excluding all the known high risk factors such as anemia, hypertension, antiphospholipid antibody syndrome, medical disease, dietary habit, living style, parity, and BMI. The collected samples at the time of delivery/after delivery were analyzed for OCPs levels by gas chromatography and polymorphic analysis for GSTM1/GSTT1 gene using multiplex PCR., Results: Significantly higher levels of α,β,γ-HCH and p,p'-DDT were found in maternal blood and significantly higher levels of β and γ-HCH and p,p'-DDT were found in cord blood of FGR cases as compared to controls. The genotypic distribution of GSTM1/GSTT1 was almost similar in both the groups, but the frequency of GSTM1-/GSTT1- (null) genotype was significantly higher in FGR cases as compared to controls (p<0.05, OR=6.42). When interaction between GSTM1/GSTT1 genes polymorphism-OCPs levels and birth weight (gene-environment interaction) was ascertained, a significant association was seen between β-HCH and GSTM1- genotype with reduction in birth weight of 213g., Conclusion: Higher levels of OCPs in pregnant women may be considered as an important aetiological factor in 'idiopathic' FGR. GST polymorphism can influence the relationship between prenatal exposure to pesticides and FGR. The present study provides evidence that polymorphism in xenobiotic metabolising genes may modify the effect of environmental health hazards and increase the risk of FGR., (Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.)

Pesticide exposure has been implicated as an environmental risk factor for the development of Parkinson's disease (PD). However, few studies have identified specific pesticides. Previously, we identified elevated serum levels of the organochlorine pesticide β-hexachlorocyclohexane (β-HCH) in PD patients from a small clinical sample. Here, we conducted a case-control study to confirm the association between β-HCH and PD in a larger sample size (n=283) with serum samples of PD patients and controls obtained from UT Southwestern Medical Center and Emory University. Samples were obtained from two discrete periods at both sites, 2001-2003 and 2006-2008, and were analyzed for β-HCH levels. Adjusted odds ratios (ORs) for PD were estimated using logistic regression and generalized estimating equations. The mean serum β-HCH level across all cohorts in this study was 22.3 ng/mg cholesterol (range: 0-376.7), and the levels were significantly higher and samples collected in 2001-2003 vs. 2006-2008. After controlling for age and gender, the OR for increased risk of PD for every 1 ng/mg increase in serum β-HCH ranged from 1.02 to 1.12 across the four different cohorts, and 1.03 (95% CI: 1.00-1.07, p value=0.031) in the pooled analysis. Furthermore, the OR for increased risk of PD of subjects having serum β-HCH levels above the inter-quartile range of 39.08 ng/mg cholesterol was 2.85 (95% CI: 1.8, 4.48; p value<0.001). These data are consistent with environmental decreases in β-HCH levels between 2001 and 2008, but they indicate that elevated levels of serum β-HCH are still associated with heightened risk for PD., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Intra uterine growth retardation (IUGR) is a major complication of pregnancy, affecting ∼5% to 10% of newborns. Hexachlorocyclohexane (HCH) is an organochlorine pesticide that consists of eight stereoisomers and γ-isomer is the only isomer that possesses insecticidal activity. The aim of the present study was to analyze the OCP residues in maternal and cord blood of women and to assess the level of oxidative stress markers as well as to establish correlation with OCP levels. Fifty women delivering neonates with low birth weight (IUGR) and equal number of women delivering normal birth weight babies (control) were recruited. We have observed higher levels of γ-HCH and T-HCH and increased oxidative stress markers in IUGR subjects versus control subjects. Significant correlations were also found between HCH isomers and oxidative stress markers in IUGR subjects. In conclusion, our results suggest that higher levels of HCH isomers may be associated with IUGR and increased oxidative stress., (Copyright © 2011 Elsevier Inc. All rights reserved.)

It has been suggested that prenatal exposure to some organochlorine compounds (OCs) may adversely affect thyroid function and may, therefore, impair neurodevelopment. The main aim of this study was to examine the relationship of cord serum levels of 1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane (4,4'-DDT), 1,1-dichloro-2,2-bis(4-chlorophenyl)ethylene (4,4'-DDE), β-hexachlorocyclohexane (β-HCH), hexachlorobenzene (HCB), four individual polychlorobiphenyl (PCB) congeners (118, 138, 153, and 180), and their sum, with neonatal thyroid stimulating hormone (TSH) levels in blood samples in a mother-infant cohort in Valencia, Spain. This study included 453 infants born between 2004 and 2006. We measured OC concentrations in umbilical cord serum and TSH in blood of newborns shortly after birth. Associations between neonatal TSH levels and prenatal OC exposure adjusted for covariates were assessed using multivariate linear regression analyses. Neonatal TSH levels tended to be higher in newborns with β-HCH levels in umbilical cord above 90th percentile (104 ng/g lipid) than in those with levels below the median (34 ng/g lipid), with an adjusted increment in neonatal TSH levels of 21% (95% confidence interval=-3, 51; P=0.09). No statistically significant association was found between the remaining OCs and TSH at birth. Prenatal exposure to β-HCH may affect neonatal thyroid hormone status and its function in neurological development.

Background: Dichlorodiphenyldichloroethylene (DDE) and other organochlorines suppress immunity biomarkers in animals and humans. Our aim was to study the association between prenatal levels of DDE and lower respiratory tract infection in infants independently from polychlorinated biphenyls (PCBs) and other organochlorines., Methods: Maternal levels of p'p'-DDE, dichlorodiphenyltrichloroethane (p'p-DDT), PCB congeners 28, 118, 138, 153, and 180, hexachlorobenzene, and beta-hexachlorocyclohexane were measured in first trimester serum of 584 pregnant women from a general population-based cohort in Sabadell (Catalonia, Spain). Mothers reported lower respiratory tract infection in interviewer-led questionnaires administered at infant age 6 and 14 months., Results: Thirteen percent of babies had recurrent lower respiratory tract infection during the first 14 months of life. Among the organochlorines, DDE showed the highest levels (median = 112 ng/g lipid); dichlorodiphenyltrichloroethane was not detectable. The median total PCB level was 85 ng/g. DDE was the only organochlorine that showed an association with recurrent lower respiratory tract infection (at levels >83 ng/g, the first tertile, relative risk = 2.40 [95% confidence interval = 1.19-4.83]), lower respiratory tract infection at 6 months (1.68 [1.06-2.66]), and lower respiratory tract infection at 14 months (1.52 [1.05-2.21]). Adjusting for PCBs, hexachlorobenzene or beta-hexachlorocyclohexane did not confound the association., Conclusions: Immunologic suppression by DDE as observed in experimental studies could explain the relation between DDE and lower respiratory tract infection, independently of PCBs. Exposure to DDE during prenatal life could be critical for the development of the immune and respiratory systems.

The paper presents the results of laboratory monitoring pesticide residues in the environment in the Republic of Mordovia in 2000 to 2007. It gives examples how to determine organic chlorine pesticides in the foodstuffs and environment, by stating the concentrations of ingredients. The entry route of pesticides and their action on human beings are shown. The main preventive measures are indicated for persons handling pesticides.

Objectives: Organochlorine pesticides (OCPs) have been reported to cause adverse reproductive outcomes. Hence, the present study was conducted to estimate and compare the levels of OCPs in maternal and cord blood of preterm labor and full term labor cases as well as assess their role in preterm delivery., Design and Methods: 23 cases each of preterm labor and full term labor were included in the study. Maternal and cord blood OCP levels were determined by using a GC-MS equipped with an electron capture detector., Results: Maternal and cord blood levels of alpha-HCH, beta-HCH, gamma-HCH, total-HCH, p,p'DDE and p,p'DDT were found higher in preterm labor than full term labor cases. However, a statistically significant relation was observed between preterm birth and beta-HCH levels only., Conclusions: Higher blood levels of beta-HCH may be associated with risk of preterm labor.

Morphological, histochemical, and histoenzymatic studies were employed to study the morphogenetic features of acetate-induced gastric ulcer in 40 rats during chronic enteral administration of the organic chlorine pesticide hexachlorocyclohexane. The authors first established the structural and metabolic bases of mucosal regeneration defects in the region of an ulcer upon chronic enteral exposure to the toxic agent and the dose dependence of the chronic nature of acute gastric ulcer.

Children encounter pesticide products and their residues where they live and play and in the food supply. Pesticide exposure affects pediatric health both acutely and chronically; effects range from mild and subtle to severe. Pediatricians play an important role in identifying and reducing significant pesticide exposure in their patients by taking an exposure history to clarify the extent and types of exposures that may have occurred during acute care and preventive care visits. Developing knowledge about the toxicity of various chemicals, identifying reliable resources for pesticide information, and providing a common-sense approach toward recommending the safest practical alternatives is necessary.

Lindane (gamma-benzene-hexachloride) has been widely used as an antiscabetic and a pediculicidal agent for the past 50 years with reasonably good efficacy. After its initial use as a first-line therapy, there have been several reports of its neurotoxicity, especially among infants and young children. Literature review reveals that the risk of its neurotoxicity is minimal if used properly and strictly according to the prescribed recommendations. However, following availability of other safer and equally efficacious alternatives, it is now being regarded as a second-line therapy for scabies and pediculosis.

(1) Cutaneous application of lindane carries a risk of systemic adverse effects, including serious neurological disorders. Lindane is readily absorbed through the skin, especially damaged skin and in children. (2) In practice, lindane has no place in the treatment of either lice or scabies.

Lindane (gamma benzene hexachloride) is a widely prescribed topical scabicide because of its efficacy and cost-effectiveness. Although toxicity from a single proper application of lindane is generally not observed, the hazards of repeated applications, industrial exposure, and accidental ingestion have been well documented. We herein describe an infant with reversible neurotoxicity following repeated applications of 1% lindane for the treatment of scabies. The role of factors predisposing to increased absorption and the recommendations to minimize potential neurotoxicity are emphasized.

Organochlorine pesticides have been used in Mexico in agriculture as a seed dresser, in sanitation, in malaria control programmes and in livestock to combat ectoparasites. The pesticides applied drift to areas where cattle graze and plants grow. Because of their chemical stability, they accumulate in the lipid-rich tissues of the body. In the body, they circulate throughout all compartments and accumulate in adipose fat. The aim was to monitor the organochlorine pesticide levels in bovine muscle fat and kidney fat from cows living in an endemic malaria zone, where the environmental contamination can be suspected as being higher. Two hundred samples (100 muscle fat, 100 kidney fat) were analysed by gas chromatography. From the pesticides, only hexachlorobenzene (HCB), beta-hexachlorocyclohexane (HCH), gamma-HCH, pp'-1.1.1-trichloro-2,2-bis(4-chlorophenyl)ethane (DDT), op'-DDT and pp'-DDE, were detected frequently and at levels above the detection limits. The HCB mean level was low at 0.009 mg kg(-1) on a fat basis. From the HCH isomers, beta-HCH mean concentration was 0.039 mg kg(-1) and gamma-HCH was 0.025 mg kg(-1) on a fat basis. Among DDTs, pp'-DDT was the major constituent (0.032 mg kg(-1) on a fat basis) followed by pp'-DDE (0.025 mg kg(-1) on a fat basis) and op'-DDT (0.023 mg kg(-1) on a fat basis). The DDT total (sigma DDT) level was 0.067 mg kg(-1) on a fat basis. Comparing the previous study (1994) and the present one (2002-03), organochlorine pesticide levels were decreased. HCB decreased 3.7 times from 0.033 to 0.009 mg kg(-1) on a fat basis; beta-HCH decreased 3.8 times from 0.149 to 0.039 mg kg(-1) on a fat basis; pp'-DDE did not reveal a significant difference at 0.026 versus 0.025 mg kg(-1) on a fat basis. However, pp'-DDT decreased substantially, 6.7 times from 0.215 to 0.032 mg kg(-1) on a fat basis. The DDT total decreased 3.5 times from 0.236 to 0.067 mg kg(-1) on a fat basis. The tendency for reduced concentrations in organochlorine pesticide levels in Mexican cows is caused by their substitution with pyrethroids used in agriculture and by the Mexican Ministry of Health in sanitary programmes.

Objective: To study the relationship between organochlorine and colorectal cancer., Methods: With multistage cluster random sampling, 11 towns were drawn based on the standardized incidence of colorectal cancer. Administrative and natural villages were drawn subsequently. Rice and soil samples in the paddy fields were collected in the villages. The contents of organochlorine were detected. Rank correlation analysis was performed together with the data of colorectal cancer incidence., Results: The contents of hexachlorocyclohexane (HCH) and dichlorodiphenyltrichloroethane (DDT) in both rice and soil samples were below the amounts of the country. Statistics showed that the standardized incidence rates were significantly different among the 11 towns. The contents of delta-HCH, gamma-HCH, sodium pentachlorophenate in rice and those of delta-HCH in soil were statistically different among the towns through the rank sum test. The standardized incidence of colorectal cancer was significantly connected with the content of total DDT in rice while rectal cancer with total DDT and PP'-DDE and colon cancer with 1245 of polychlorinated biphenyl (PCBs). The correlation coefficients were 0.636, 0.691, 0.716 and 0.658 respectively (P < 0.05)., Conclusions: Rectal cancer was statistically correlated with organochlorine, mainly for total DDT and dichlorodiphenyldichloroethylene (PP'-DDE). Colon cancer was significantly associated with 1245 of PCBs. Further study should be performed since this research was only an ecological study.

Head lice infestation is a common and growing problem that primarily affects school-aged children. Most cases of head lice are diagnosed and treated by nonphysicians. Misdiagnosis may lead to treatment when no lice are present. Treatment failure may lead to repeated use of and improperly applied pediculicides, potentially resulting in overexposure to pesticides. These treatment failures are primarily due to the emergence of treatment-resistant lice. In regions where resistant lice are common, patients may self-treat numerous times with over-the-counter pediculicides before seeking treatment from a physician. Resistance has decreased the efficacy of lindane, a prescription pediculicide that has been used for decades. In addition, the Food and Drug Administration recently warned of potentially serious adverse effects associated with lindane and recommended strict controls for its use. Malathion, recently reintroduced in the United States as a prescription pediculicide, has not been associated with treatment resistance or notable adverse effects, although it is flammable due to its alcohol base. Because of concerns about decreasing efficacy due to resistance and safety concerns about over-the-counter products and some prescription pediculicides, a reassessment of pediculicide safety is warranted. The safety and efficacy of commonly used over-the-counter and prescription pediculicide products are discussed, along with the safety and efficacy of other treatments, such as ivermectin, that are not indicated for the treatment of head lice but are being used increasingly.

Background: Lindane (gamma-benzene hexachloride), commonly used as a treatment for pediculosis, has been associated with adverse reactions and has recently undergone increased regulation., Objective: We sought to describe the patterns of a large number of lindane exposures reported to poison centers in Texas during 1998-2002., Methods: Data on all lindane exposures for pediculosis reported to the Texas Poison Center Network were analyzed., Results: There were 528 reported human exposures to lindane for pediculosis. The incidence of lindane exposures has decreased by 52% from 1998 to 2002. Misuse or abuse of lindane was reported in at least 87% of the cases. Of those cases with a known patient age, 45% were less than age 6 yrs, 23% age 6-19 yrs, and 32% over age 19 yrs. Female patients accounted for 55% of reported cases. Of those cases with a known medical outcome, 61% reported no effects. The most frequently reported symptoms were vomiting, nausea, and ocular irritation or ocular pain., Conclusion: The number of reported lindane exposures in Texas is decreasing. The majority of reported exposures involve misuse or abuse of the product. The pattern of symptoms reported in Texas was consistent with the literature.

Daily intake of lead, cadmium, aluminium, radiocaesium, DDT and metabolites, and lindane in the whole-day food rations collected in hospital canteens in Kraków, Łódź, Olsztyn and Poznań in winters of 1993-1994, 1995 and 1996 were determined. The diets contained almost 40 microg of cadmium, corresponding to 70% of PTWI, and compared to the levels recognised as safe (ADI or PTWI) small amounts of the other contaminants. The highest content of Pb, Cd, Al and lindane was determined in the diets collected in Kraków, that of radiocaesium in Łódź, and DDT level was the highest in Poznań. The whole-day food rations from Olsztyn, situated in a region called "green lungs of Poland", were not statistically less contaminated than the diets from the other towns. The Pb and radiocaesium levels decreased significantly with time.

Contamination of persistent organochlorines (OCs) such as PCBs (polychlorinated biphenyls), DDT and its metabolites (DDTs), HCH (hexachlorocyclohexane) isomers (HCHs), chlordane compounds (CHLs), and HCB (hexachlorobenzene) were examined in mussels collected from coastal waters of Asian countries such as Cambodia, China, Hong Kong, India, Indonesia, Japan, Korea, Malaysia, Philippines, Far East Russia, Singapore, and Vietnam in 1994, 1997, 1998, 1999, and 2001 to elucidate the contamination status, distribution and possible pollution sources and to assess the risks on aquatic organisms and human. OCs were detected in all mussels collected from all the sampling sites investigated. Considerable residue levels of p,p(')-DDT and alpha-HCH were found in mussels and the concentrations of DDTs and HCHs found in mussels from Asian developing countries were higher than those in developed nations suggesting present usage of DDTs and HCHs along the coastal waters of Asian developing countries. On the other hand, lower concentrations of PCBs detected in mussels from Asian developing countries than those in developed countries indicate that PCBs contamination in mussels is strongly related to industrial and activities. To our knowledge, this is a first comprehensive report on monitoring OCs pollution in the Asia-Pacific region.

Objective: To examine the association between DDT (dichlorodiphenyl trichloroethane) and HCH (hexachlorocyclohexane) exposure and intra-uterine growth retardation (IUGR, <10th percentile of birth weight for gestational age)., Method: We detected p,p'-DDT, o,p'-DDT, p,p'-DDD, p,p'-DDE and alpha-HCH, beta-HCH, gamma-HCH, delta-HCH in maternal blood, placenta and cord blood, collected at parturition, from mothers with IUGR babies ( n=30) and from those with babies of normal weight ( n=24), using gas-liquid chromatography equipped with electron capture detector ((63)Ni). The adjusted odds ratios (ORs) for these pesticides in mothers and infants were determined by multiple logistic regression., Results: There were statistically significant associations ( P<0.05) between maternal blood levels of alpha-HCH (OR=1.22; 95% CI: 1.02-1.46), gamma-HCH (OR=1.38; 95%CI: 1.05-1.80), delta-HCH (OR=1.61; 95% CI: 1.01-2.54), total HCH (OR=1.07; 95% CI: 1.01-1.13) and p,p'-DDE (OR=1.21; 95%CI:1.03-1.42) and IUGR after adjustment for potential confounders. Also, significant association (P<0.05) between cord blood levels of gamma-HCH (OR=1.14; 95% CI: 1.00-1.31), delta-HCH (OR=1.31; 95% CI: 1.00-1.75), total HCH (OR=1.07; 95% CI: 1.00-1.14) and IUGR were found after adjustment for potential confounders. A significant negative correlation between body weight of newborn babies and p,p'-DDE in maternal blood (r= -0.25; P<0.05) and delta-HCH and p,p'-DDE in the cord blood (r= -0.27 and -0.26; P<0.05) was noticed after gestational age had been accounted for., Conclusion: Exposure of pregnant women to organochlorine pesticides may increase the risk of IUGR, which is a contributing factor for infant mortality in India.

In this laboratory study, we address the effect of Chironomus bioturbation (0, 2,000, 6,000, and 18,000 ind/m2) and sediment organic matter content (10, 20, and 40%) on the fate, distribution, and bioavailability of 14C-lindane under standardized conditions in toxicity tests with artificial sediment. The results show that both Chironomus burrowing activity and sediment organic matter strongly modify test conditions. Larval mortality and development were inversely related with Chironomus densities and lindane concentration. Sediment organic matter content affected larval development rates but not mortality. Partitioning of lindane between the sediment, overlying water, and interstitial water was affected negatively by Chironomus larval densities: however, sediment partitioning was positively affected by sediment organic matter content. Bioturbation by Chironomus resulted in a remobilization of particle-associated lindane to the interstitial and overlying water, implying an increase in the bioavailability of the test compound. Strong positive relationships were found between Chironomus densities and lindane concentrations in interstitial water. The presence of Chironomus also resulted in lower label recovery. Label recovery on sediment particles ranged from 49 to 61% of initially added label in microcosms without Chironomus, from 41 to 56% at low larval densities, and from 15 to 50% at high larval densities. These results show that large discrepancies may exist between nominal test concentrations (from test compound additions) and true exposure concentrations even under standardized test conditions, which can introduce a relatively large error term in risk assessments. Calculations show that volatilization may be a quantitatively important sink for test compounds.

The authors studied the in vitro effects of lindane on macrophage-activating factor (MAF) production by peripheral blood leukocytes (PBLs) in rainbow trout. MAF production by PBLs induced normally by mitogens concanavalin A (ConA) and phorbol myristate acetate (PMA) was not modified by a pretreatment with lindane (from 2.5 to 50 microM). Only a concentration of 100 microM lindane decreased MAF production, associated with cellular death. Moreover, MAF activities were detected in supernatants of PBL cultures treated with lindane from 2.5 to 10 microM in absence of ConA/PMA stimulation. Factors present in these supernatants remain to be identified. Lindane, at concentrations which did not induce MAF production (50 and 100 microM) led to an increase in PBL calcium levels by acting on the endoplasmic reticulum calcium stores. Although the intracytosolic calcium concentration ([Ca(2+)](i)) increase seems to be associated with cell death, lindane-induced MAF production may be linked with other intracellular mechanisms.