V. K. Bhatnagar

Assessment of thyroid function in pesticide formulators.

Thirty male pesticide formulators exposed to the dust and liquid formulation of endosulfan, quinalphos, chlorpyriphos, monocrotophos, lindane, parathion, phorate, and fenvalerate and 20 comparable control subjects from the same area of study were examined for the evaluation of thyroid function tests. The level of TSH was elevated (about 28%) in pesticide formulators as compared to a control group, but the increase was statistically insignificant. Based on the individual TSH measurement, 3 of 30 formulators had isolated elevated levels of TSH and seem to have acquired sub-clinical hypothyroidism; five had TSH values slightly elevated to the upper boarder line (4.03,uIU/ml); and the majority of formulators (N= 22) had TSH values in the normal range varying from 1.29 to 3.9 pIU/ml. Total T3 was suppressed significantly (P <0.01) in formulators, while marginal decrease (about 7%) was noticed in T4 level. This studyindicatedthyroidfunctionimpairmentinfewpesticide formulators.

Levels of organochlorine insecticides in human blood from Ahmedabad (rural), India

Assessments of human exposure to persistent organochlorine insecticides (OCI) through biological monitoring offers a profound criteria to evaluate the magnitude of potential health risk, if any, due to use of these chemicals. Residues of these chemicals especially DDT and HCH have been identified and reviewed in man and his environment from different parts of the world however, by comparison very high levels of DDT and its metabolites have been reported in human body fat, blood and milk samples in India. Since there is a definite relationship between the amount of DDT and its residues in blood and those present in human fat depot, blood can be easily be used for assessing the total body burden of persistent OCI in various populations. In view of fragmentary reports on the levels of DDT and HCH in human blood samples from India which categorically pertain to the general population of urban areas like Delhi and Lucknow. The authors attempted to provide a database on residues of DDT and HCH including other cyclodiene compounds, e.g. heptachlor, heptachlor epoxide, aldrin, oxygchlordane, HCB and dieldrin in blood samples collected from general population of Ahmedabad (rural) area.

Repeated episodes of endosulfan poisoning

Introduction: a number of families in a rural area of Jabalpur District (Madhya Pradesh), India, were affected by repeated episodes of convulsive illness over a period of three weeks. The aim of this investigation was to determine the cause of the illness. Methods: the investigation included a house‐to‐house survey, interviews of affected families, discussions with treating physicians, and examination of hospital records. Endosulfan poisoning was suspected as many villagers were using empty pesticide containers for food storage. To confirm this, our team collected blood and food samples, which were transported to the laboratory and analyzed with GC‐ECD. Results: thirty‐six persons of all age groups had illness of varying severity over a period of three weeks. In the first week, due to superstitions and lack of treatment, three children died. In the second week, symptomatic treatment of affected persons in a district hospital led to recovery but recurrence of convulsive episodes occurred after the return home. In the third week, 10 people were again hospitalized in a teaching hospital. Investigations carried out in this hospital ruled out infective etiology but no facilities were available for chemical analysis. All persons responded to symptomatic treatment. The blood and food samples analyzed by our team showed presence of endosulfan, which was confirmed by GCMS. One of the food items (Laddu) prepared from wheat flour was found to contain 676 ppm of α‐endosulfan. Conclusions: Contamination of wheat grains or flour with endosulfan and its consumption over a period of time was the most likely cause of repeated episodes of convulsions, but the exact reason for this contamination could not be determined. This report highlights the unsafe disposal of pesticide containers by illiterate farm workers, superstitions leading to delay in treatment, and susceptibility of children to endosulfan.

Cardiac Toxicity Following Short-Term Exposure to Methomyl in Spraymen and Rabbits

A health surveillance study in 22 healthy spraymen showed significent T-wave changes (including inversion) in most of the limb leads and chest leads following 5 d exposure to methomyl, a carbamate pesticide. Significant changes in plasma cholinesterase and lactic dehydrogenase activities were also noticed. The ECG changes could be reproduced in rabbits and were dose dependent. This type of ECG change following exposure to a carbamate compound is reported for the first time in occupationally-exposed subjects. The study results indicate that these changes are probably directly related to methomyl rather than its toxicity through cholinesterase inhibition. The significance of these changes remain to be investigated.

Integrated pest management and residue levels of dichlorodiphenyltrichloroethane (DDT) and hexachlorocyclohexane (HCH) in water samples from rural areas in Gujarat State India.

Abstract The authors identified 2 rural areas for study in Gujarat State, India, on the basis of pesticide use in agriculture and vector-control programs. In rural area 1, pesticides were used in both agriculture and vector-control programs, whereas in rural area 2, they were used in agriculture only. Water samples were collected from both areas, and they were analyzed for total dichlorodiphenyltrichloroethane (DDT) and hexachlorocyclohexane (HCH) residues. The mean residue levels of total DDT in rural areas 1 and 2 were 7.56 ng/l and 4.27 ng/l, respectively. The corresponding values for HCH were 6.96 ng/l and 5.53 ng/l, respectively. Residue levels of both pesticides were significantly lower in rural area 2 than in area 1.