Effects of exposure to lead among lead-acid battery factory workers in Sudan.

Health effects of occupational exposure to lead were investigated among 92 exposed workers in lead-acid battery factory and 40 nonexposed workers serving as a control group from an oil mill in Khartoum North industrial area. The two groups were closely similar in age, stature, body weight, and socioeconomic conditions. A highly significant increase (P less than .01) was recorded in blood lead, urinary coproporphyrin, and basophilic stippled red blood cells of the exposed group in comparison to the control group. Central nervous system symptoms (insomnia, fatigue, weakness, and drowsiness) were reported by 50% and other symptoms such as abdominal colic and constipation were reported by 41% of the exposed group. Blue line on the gum was detected only on 2% of the exposed group. Strong associations between exposure to lead and the prevalence of central nervous system symptoms, abdominal colic, and constipation were recorded. Exposure to exceedingly high levels of lead in the working environment causes adverse health effects.

The effect of the herbicide atrazine on rhizosphere microflora of broad bean plants, infested with Fusarium oxysporum f. fabae and Rhizoctonia solani.

The effect of the herbicide atrazine on Fusarium oxysporum f. fabae and Rhizoctonia solani, the causative agents of wilt and rot, respectively, as well as rhizosphere microflora of broad bean plants was studied. The herbicide was applied at intervals of 30, 20, 10, and 0 days before sowing. Atrazine application reduced both densities and per cent of infection of these two pathogenic fungi, R. solani, however, was sensitive to atrazine itself, while F. oxysporum was affected by atrazine by-products. Rhizosphere flora, i.e., total microbial flora, actinomycetes, phosphate-dissolving bacteria, and fungal flora, were not affected by atrazine, but were deleteriously reduced by its by-products at early stages of plant growth. However, rhizosphere flora attained the normal levels after atrazine by-products had completely disappeared from soil (1 month after application), except for actinomycetes. Therefore, it is recommended to apply atrazine within 20 days before sowing for weed control as well as for controlling wilt and root rot infestations.

Changes in metabolic activities of Fusarium oxysporum f. fabae and Rhizoctonia solani in response to Dithan A-40 fungicide.

The effect of different concentrations of Dithan A-40 fungicide on the metabolic activities of the wilt fungus Fusarium oxysporum f. fabae and the root rot agent Rhizoctonia solani was studied. All toxicant concentrations reduced energy generation, total phosphorus and nitrogen content of both fungi. In addition, the toxicant caused a shift in free amino acids pool. As a result of these changes, the mycelium dry weight of both fungi was greatly reduced. R. solani was more sensitive to the toxic effect of Dithan A-40 than F. oxysporum.