A group of 18 male Caucasian workers from the United Kingdom and a further group of 18 male mixed race (mainly Malay) workers from Malaysia employed in the formulation of paraquat-based herbicides were examined for evidence of chronic ill health after long-term exposure to paraquat. Clinical records were examined, medical and occupational histories were obtained and a clinical examination, particularly of the skin, was undertaken. Skin rashes, nail damage and epistaxes were encountered by most workers as a result of direct contact of skin and mucous membranes with paraquat. These conditions subsided rapidly and no worker reported any sequelae. There was no clinical evidence of long-term effects on skin, mucous membranes or general health following exposure to paraquat over several years in these workers.
Tests of pulmonary function (FVC, FEV1, FEV 1%, and single breath CO diffusion), renal function (serum creatinine and BUN), liver function (serum ALT, AST, and ALKP) and a full haematological screen were performed on 27 paraquat spraymen (mean spraying time 5.3 years; mean individual annual quantity of paraquat handled, 67.2 kg as paraquat ion) and on two control groups. One of the control groups consisted of 24 general plantation workers with minimal exposure to paraquat arising from occasional work in recently sprayed areas, and the second consisted of 23 latex factory workers with no known occupational exposure to paraquat. The results showed no significant differences as a consequence of occupational exposure to paraquat. Long-term paraquat spraying at the concentrations used produced to quantifiable harmful effects on health as measured by the indices selected for this study.