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Eudrilus eugeniae, the vermicomposing worm, is found in considerable numbers in agricultural fields in India due to their eventual transfer through vermimanure. These worms are very often exposed to pesticides, herbicides, chemical fertilisers and other soil amendments. This paper reports the effects of variable concentrations of urea, phosphogypsum (PG), paper mill sludge (PMS) and two organophosphorus agrochemicals, monocrotophos and glyphosate, on certain morphological, histological and biochemical parameters of E. eugeniae. Results indicated setal anomalies, epidermal lesions, clitellar swelling and constriction of the body. Disintegration of connective tissue, vacuolation of dermis and significant alterations in protein, lipid peroxidation levels and activities of lactate dehydrogenase, acetylcholinesterase and catalase have also been observed in the treated worms. It is proposed that setae, connective tissue, protein and enzymes in E. eugeniae could be useful markers to evaluate toxicity due to the test chemicals.

Heavy metals known to be accumulated in plants adversely affect human health. This study aims to assess the effects of agrochemicals especially chemical fertilizers applied in paddy fields, which release potential toxic heavy metals into soil. Those heavy metals get accumulated in different parts of paddy plant (Oryza sativa L.) including the grains. Concentrations of nonessential toxic heavy metals (Cd, Cr, and Pb) and the micronutrients (Cu, Mn, and Zn) were measured in the paddy field soil and plant parts. Mn and Cd are found to be accumulated more in shoot than in root. The metal transfer factors from soil to rice plant were significant for Pb, Cd, Cu, Cr, Mn, and Zn. The ranking order of bioaccumulation factor (BAF) for heavy metals was Zn > Mn > Cd > Cu > Cr > Pb indicating that the accumulation of micronutrients was more than that of nonessential toxic heavy metals. The concentrations of heavy metals were found to be higher in paddy field soils than that of the nearby control soil but below permissible limits. The higher Health Index (HI) values of rice consuming adults (1.561) and children (1.360) suggest their adverse health effects in the near future.

We studied chronic fluoride intoxication in 10 villages of Udaipur receiving F emissions from phosphate fertilizer factories. Although fluoride remained below permissible limit in most of the drinking water samples, the incidence of fluorosis in adults as well as in children was surprisingly high. Khemli appeared to be the most affected village (with >48% cases) where, about 93% of 2 h air samples contained fluoride above 2.0 μg m(-3) and crops and vegetable F ranged from 27.5 to 143.4 μg g(-1). Concentrations of fluoride and inorganic P in urine showed asynchrony and were well linked with prevalence of fluorosis. The study indicated that air-borne fluoride was the major factor for higher prevalence of fluorosis in these rural areas.

The effects of air pollution on plants downwind of a fertilizer factory at Udaipur, India, were studied using three woody perennials. Seedlings of these species including a shrub (Carissa carandas L.), a leguminous avenue tree (Cassia fistula L.) and a fruit tree (Psidium guajava L.) were grown in earthen pots at different study sites receiving varying levels of air pollution input. Changes in plant growth, morphological characteristics, photosynthetic pigment, ascorbic acid, N and S contents and in dry matter allocation were considered in relation to the status of ambient air quality. Observations with these parameters have indicated that the ambient air around the factory contained pollutants at phytotoxic levels. Plant height, basal diameter, conopy area, leaf area and chlorophyll, ascorbic acid and foliar-N concentrations decreased with increasing pollution load. However, foliar-S increased slightly at polluted sites. Air pollution load around the factory have also altered the biomass allocation. Root:shoot ratios increased in C. fistula and P. guajava at polluted sites. In contrast, for C. carandas the above ground parts, where foliage assumed predominance showed precedence over the root growth. This species responded characteristically to air pollution stress by allocating more of its photosynthate towards leaf production and shoot growth.

Tea in Darjeeling foothills and terai are grown conventionally, with application of chemical fertilizers and pesticides, as well as organically without these inputs. Ground level arthropod community was collected from the above two types of tea plots using pitfall traps. Catches from these environments showed variation in the arthropod faunal structure with numerically and taxonomically greater abundance in the organic than that of the conventional plot. Coleopterans were more diverse with largest number of families and Recognizable Taxonomic Units (or morphospecies) in the organic tea plot. The diversity and similarity indices for coleopterans were comparable, in organic and conventional tea plots at species and family levels. The close relationship of the indices suggested that diversity study at family level could be used as surrogate for species level diversity; thus alleviating the laborious and expertise job of taxonomic identification of arthropod species. Faunal diversity study at ground level gave the clue that soil of the organic plantation was healthier than that of the conventional tea plot.