Introduction:
Patulin is a mycotoxin produced by a variety of moulds, for instance, Aspergillus, Penicillium and Byssochlamys, and found most often in rotten apples. Previous studies showed toxic effects of patulin in the gastro-intestinal tract, impairment of kidney function, as well as neurotoxicity.

Objective:
The aim of the study was to investigate whether intoxication with patulin affects the activity of acid phosphatase, cathepsin B and D in mice kidneys and livers.

Material and methods:
method. Experiments were conducted on 36 female mice. Animals were divided into 6 groups of 6: 1 – control, 2 – received 0.1 LD50 patulin i.p. 28 days, 3 – saline i.p. once, 4 – patulin i.p. 0.1 LD50 once, 5 patulin i.p. 0.2 LD50 once, 6 – patulin i.p. 0.5 LD50 once. 6 hours after patulin or saline administration, animals from groups 3, 4, 5, 6 were sacrificed. Kidneys and livers were obtained. Animals from groups 1 and 2 were sacrificed on day 29. Acid phosphatase activity was measured in the tissue supernatants with colorimetric method. Cathepsin B and D activities were determined with an ELISA-kit.

Results:
The activities of acid phosphatase, cathepsin B and D in the kidneys and livers of mice exposed to patulin for 28 days was higher than in controls. A proportionate increase in acid phosphatase and cathepsin B activity in the kidneys and livers was observed for a single dose of the xenobiotic.

Conclusions:
Acute and subacute poisoning with patulin negatively affects the functioning of lysosomes and induces an increase in the activity of lysosomal enzymes in mice livers and kidneys. Activities of acid phosphatase and selected cathepsins in the livers and kidneys are markers of cell damage due to patulin’s toxicity.