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T D Seth

Publications and source records attributed to T D Seth.

At least 19 recordsLinked to original sources
PubMed1994

The role of reactive oxygen species in the degradation of lindane and DDT.

We have studied the photodegradation reactions of lindane and DDT under sunlight (72 hr) or a solar simulator (2 hr) either directly or in presence of selected photodynamic sensitizers. Direct photolysis did not cause noticeable degradation of the pesticides (below 1% in both the cases). However, addition of benzophenone or rose bengal to the irradiation solution of lindane resulted in 88% and 47% degradation, respectively, under sunlight. Similar experiments carried out with DDT resulted in 89%, 50% and 32% degradation with benzophenone, rose bengal and methylene blue, respectively. All the photosensitizers used for the study have been shown to induce photooxidation reactions by generation of reactive oxygen species. These studies suggest that by employing certain naturally occurring photosensitizers with reactive oxygen generation potential under sunlight, an effective method for safe removal of pesticides and other environmentally persistent agents from the surface of earth can be developed.

Anthracenes↗
PubMed1985

Organochlorine pesticide residues in mother's milk: a source of toxic chemicals in suckling infants.

A total of 24 samples of mother's milk collected during the first week of lactation from four major cities in India (Karnal, Bangalore, Calcutta and Bombay) were analysed for the estimation of organochlorine pesticides (OCPs). alpha-HCH, p,p'-DDE, and p,p'-DDT were generally the main contaminants. The average total 1,1,1-trichloro-2,2-bis (p-chlorophenyl) ethane (DDT) levels stand at 0.05, 0.11, 0.19 and 0.22 p.p.m. (whole-milk basis) in the samples from Bangalore, Calcutta, Karnal and Bombay respectively. In the same order total hexachlorocyclohexane (HCH) levels were around 0.01, 0.03, 0.03 and 0.05 p.p.m. Wide variations among OCP levels observed in the present study have no relation with the fat content of the various samples. The samples from Calcutta and Bombay showed significantly high levels of OCPs. The daily intake of total HCH and DDT residues calculated for the suckling infant was significantly higher in the present study when compared with the WHO recommended value.

Fats↗
PubMed1981

Effect of lead and zinc administration on liver, kidney and brain levels of copper, lead, manganese and zinc and on erythrocyte ALA-D activity in rats.

Albino male rats were given lead (Pb) and zinc (Zn) orally, singly or in combination, for 14 consecutive days. Liver Pb was increased and liver manganese (Mn) was decreased in animals receiving Pb. The combination of Pb and Zn led to increased Pb and decreased copper (Cu) and Mn. Kidney Zn was increased in rats given Zn or the combination of Pb and Zn. There were no changes in kidney Cu or Mn in any group. Brain Pb levels were significantly increased in animals given Pb and Zn levels in those given Zn. Erythrocytic amino levulinic acid dehydratase (ALA-D) activity was significantly decreased by Pb but not by Pb + Zn.

Animals↗
PubMed1981

DDT and BHC residues in some body tissues of goats, buffalo, and chickens, Lucknow, India.

Muscle, liver, brain, and abdominal body fat samples of goats, buffalo, and chickens, all common meat sources in India, were analyzed by gas-liquid chromatography (GLC) for residues of DDT and benzene hexachloride (BHC). A few samples of goat and buffalo bone marrow were also included. Relatively high residue levels were found in body fat and bone marrow compared with other tissues. DDT and BHC residue levels were highest in chicken body fat, averaging 4.157 ppm sigma DDT and 3.879 ppm BHC. DDT content was much higher in goat and buffalo bone marrow than in the corresponding body fat. DDT levels in brain samples were highest (0.138 ppm) in buffalo. p,p'-TDE levels were higher than p,p'-DDE levels in buffalo; overall DDT levels were lowest in goats. BHC residues were generally low in buffalo; alpha-BHC accounted for most BHC residues in brain tissues. Greater accumulations of DDT and BHC were found in leg muscles than in breast muscles of chickens.

Animals↗
PubMed1981

Organochlorine pesticide residues in some Indian wild birds.

Residues of BHC and DDT were estimated by gas-liquid chromatographic analysis of the internal body organs, depot fat, and blood plasma of a few species of Indian wild birds, captured in and around the urban area of Lucknow. Total BHC and gamma-BHC (lindane) levels were high in breast muscle, liver, heart, and lung tissues of pigeon, crow, and vulture, compared with the respective tissues of chicken, cattle egret, and kite. More lindane and total BHC was found in tissues of vulture compared with other species. The major part of BHC isomers in the brain of birds examined was accounted for by alpha-BHC. Total BHC detected in depot fat of crows was 29.7 ppm; lesser amounts were found in vulture, kite, and cattle egret, respectively. Total DDT levels were comparable in the blood plasma of chicken, pigeon, crow, and cattle egret, although residues generally showed the following order in the tissues examined: chicken less than pigeon less than cattle egret less than crow less than kite less than vulture. High levels of DDT were detected in depot fat of crow, kite, and vulture (50.8, 67.0 and 95.3 ppm, respectively). Avian species thus reflect biological magnification of BHC and DDT residues, presumably due to their food habits.

Animals↗
PubMed1980

Role of chlorinated hydrocarbon pesticides in abortions and premature labour.

Premature labour and abortion possibly due to the high concentration of organochlorine pesticides have been investigated. Considerably higher amounts of organochlorine pesticide residues have been detected by gas liquid chromatography in the circulating blood and placental tissue of the women undergoing abortion or premature labour as compared with pregnant women in full term labour. The differences are highly significant for all pesticides estimated.

Abortion, Spontaneous↗
PubMed1980

Organo chlorine pesticides in human placenta and accompanying fluid.

Fifty specimens of placenta and accompanying fluid were collected at random from women of general population and analyzed for organo chlorine pesticides by gas liquid chromatograph using electron capture detector. BHC, Lindane, DDT, DDE, DDD and aldrin were detected in the placental tissue and accompanying fluid. Lindane, DDE and aldrin were more frequently detected. All the women were in their twenties but no correlation could be made between the compound and age, race or residence of the women. This is presumably the first attempt in India to detect the presence of pesticides in relation to their placental transfer, without occupational or accidental exposure.

Amniotic Fluid↗
PubMed1980

Effect of extent of myocardial damage on the behavior of myocardial zinc in albino rats.

The effect of the extent of myocardial necrosis on myocardial zinc was studied in albino rats. Varying degrees of myocardial necrosis were produced by subcutaneous injection of two different doses of isoproterenol (85 mg/kg body wt and 42.5 mg/kg body wt). Myocardial necrosis was confirmed by serum glutamic oxaloacetic transaminase (SGOT), serum glutamic pyruvic transaminase (SGPT), serum lactate dehydrogenase (SLDH), ECG, and histology. Myocardial zinc was depleted after the administration of isoproterenol. This depletion was proportional to the extent of myocardial damage. There was an attempt by the heart for re-uptake of zinc. However, this re-uptake could not be sustained in hearts with more extensive cardiac damage.

Alanine Transaminase↗