Farm-grade chlorpyrifos (Durmet) is genotoxic in somatic and germ-line cells of Drosophila.

The mutagenic potential of Durmet, a farm-grade formulation of chlorpyrifos, was studied in the Drosophila wing mosaic and sex-linked recessive lethal tests. Larvae of the 2nd or 3rd instar carrying suitable recessive genetic markers on chromosome 3 were exposed to different concentrations of the insecticide and the frequency of induction of mutant mosaic spots on the wings was noted. The Basc technique was followed to study the induction of sex-linked recessive lethals. On the basis of the frequency of induction of mosaic wing spots and sex-linked recessive lethals, it is concluded that Durmet is genotoxic in somatic cells as well as germ cells of Drosophila.

Studies on the genotoxicity of monocrotophos in somatic and germ-like cells of Drosophila.

Parryfos, a farm-grade formulation of monocrotophos, was tested for genotoxicity in the wing primordial cells and the male germ-line cells of Drosophila melanogaster. Larvae of the 2nd or 3rd instar, heterozygous for the wing-cell marker mutations mwh and flr3, were exposed to different concentrations of the insecticide in the food. The wings of the hatched flies were screened for the presence of mutant mosaic spots exhibiting the marker phenotypes. The frequency of induction of sex-linked recessive lethal mutations was used to assess genotoxic effects in male germ-line cells. The tested compound was genotoxic in both the somatic and the germ-line cells of Drosophila.

Mutagenicity of sumithion tested in Drosophila somatic and germ cells.

Sumithion, a broad-spectrum insecticide, was tested for its mutagenicity in the Drosophila wing-spot test and sex-linked recessive lethal test. Strains carrying the recessive mutant markers mwh and flr3 in their third chromosomes, expressed phenotypically as multiple trichomes or thickened and misshapen wing hairs in the adult wings, were used in the wing-spot test. Larvae transheterozygous for these markers were exposed to the insecticide in instant food and the sex-linked recessive lethal test was performed by the standard technique using the Basc strain. The compound is mutagenic in the wing primordial cells and induces recombination at high doses. Further, the frequency of induction of sex-linked recessive lethals is significant only at high treatment doses.

Acrylamide is genotoxic to the somatic and germ cells of Drosophila melanogaster.

The genotoxic effects of acrylamide, a recently detected carcinogen, have been studied in the somatic (wing primordia) and germ cells of Drosophila melanogaster by the wing mosaic assay and the sex-linked recessive lethal test respectively. Larvae, 72 +/- 4 h old, were exposed to 6 different concentrations of acrylamide ranging between 0.25 mM and 5.0 mM in instant medium for 48 h. It is observed that acrylamide is both mutagenic and recombinogenic in the wing disc cells and induces sex-linked recessive lethals.

Degradation of Alpha-, Beta-, and Gamma-Hexachlorocyclohexane by a Soil Bacterium under Aerobic Conditions.

A Pseudomonas sp., isolated from sugarcane rhizosphere soil, readily metabolized not only alpha and gamma isomers of hexachlorocyclohexane, but also the thermodynamically more stable beta isomer, under aerobic conditions. Bacterial degradation of the three isomers led to the accumulation of a transitory metabolite and eventual release of covalently linked chlorine as chloride in stoichiometric amounts.

Construction of growth reference standards for urban slum children in developing countries.

A cross-sectional sample of 2987 children in the age group of 1 to 10 years were selected from urban slums of Delhi for measurement of weight and height. Males and females were 53 and 47% respectively. Mean weight and height were calculated for both the sexes. Comparison of percentiles of weight and height with NCHS and ICMR standards showed that the 75th percentiles weight and height of the present study were comparable with 80 and 90% of 50th percentile of NCHS respectively. Hence, upper 25% of the sample arranged in ascending order of magnitude were used for the construction of reference standards of weight and height. Comparison of percentiles drawn from the top 25% of the sample demonstrated that 50th percentile of the present study corresponded to 80% of 50th percentile of the NCHS for weight and 90% of 50th percentile of NCHS of the height for both boys and girls. Also the 50th percentile of ICMR for weight and height for both the sexes. Standards constructed from such sample would be better suited for two important uses: (i) monitoring of Nutrition Programme, and (ii) to detect a child with abnormal growth at the earliest.