Validity of threshold limit value of malathion for chronically exposed industrial workers in Egypt

ABSTRACT

This study aimed to evaluate the currently applied threshold limit value [TLV] of malathion as a safe level for chronic exposure. This cross sectional study included all exposed workers in a factory producing malathion in Alexandria and a corresponding control group of 30 male individuals. All participants were subjected to questionnaire, clinical examination concerning cardio-neurological manifestations, ECG and measurement of RBC, plasma and total activity of cholinesterase. Air samples were analyzed by gas-liquid chromatography for malathion. Environmental air levels of malathion were below TLV. Difficulty in concentration, emotional outbursts and tremors were significant manifestations in relation to both exposure and low cholinesterase activity. A significant reduction of RBC, plasma and total activity of cholinesterase was observed for workers exposed to 8.35 mg/m3 in comparison with those exposed to other levels and controls