Environmental monitoring in Lithuania. Environmental distress signals: gastrointestinal epithelial barrier after exposure to chemical agents.

Lithuania's environment is heavily polluted as a result of domestic and transboundary contamination. The main ecological problems are related to atmospheric pollution; water contamination; soil, water, and forest acidification; nitrogen-compounds overload of soil, water, and food; and contamination with agricultural chemicals and heavy metals. The increased environmental distress is a menace to public health in Lithuania. Experimental studies need to be designed and used to ascertain the effects of environmental distress on the gastrointestinal tract epithelial barrier. Our electronmicroscopic and immunohistochemical study of human gastrointestinal endocrine cells revealed changes in the amount of secretory material and intracytoplasmic vacuolization after exposure to the environmental chemicals such as hexavalent chromium and the herbicide Saprol. The most affected were the EC (serotonin, motilin, substance P), D (somatostatin), A (glucagon), B (insulin), and mast (histamine, serotonin, heparin) cells. These results provide ultrastructural evidence of digestive tract epithelial barrier reaction as an expression of environmental distress signals of the organism.