ANÁLISE DA TOXICIDADE E ECOTOXICIDADE DE REVELADOR DE IMAGENS RADIOGRÁFICAS MÉDICAS DE HOSPITAL PÚBLICO DE GOIÂNIA (GO)

Abstract

The liquid effluent from medical radiology centers is polluting and toxic and it can result in damage to humans and to the environment when it is discarded in the sanitary sewer system without prior treatment. This study aimed to chemically analyze OBD5, OCD, silver and total sulphate and also, through bioassays, to determine the toxic potential of the waste generated during the revealing of medical radiographs. The residual sample of this waste, for this research, was collected in one of the hospitals belonging to the state of Goiás, located in its capital, Goiânia. The parameters OBD5, OCD, silver and total sulphate were analyzed in the sample with natural pH (9.9) and after its correction with HCl (1:1) to 8.5. The bioassays were performed only with the sample after pH correction and they consisted of analysis of root growth and germination seeds of Allium cepa L., and also ecotoxicological evaluation using Artemia salina. In the experiments, to evaluate the Root Growth Rate and Seed Germination Rate of Allium cepa L., revealing residual concentrations of 0; 0.5; 1; 2 and 4% (v/v) were used. In the ecotoxicological assays with Artemia salina, used to obtain the DL50, concentrations of 0; 0.25; 0.5; 1; 1.5; 2; 2.5 and 3% (v/v) were used. The results of OBD5, OCD and total sulphate (pH 9.9) were well above the permitted limits imposed by Saneago. The sample with pH 8.5 was reported to be OBD5 15% and OCD 25% higher than those found in the sample without pH correction. Yet, the concentration of total sulphate, with pH correction to 8.5 has adapted to standards of Saneago. In both analyzes with pH 9.9 and 8.5 the total silver parameter did not exceed the quality standards of Saneago for the ones to be released in the sewer system. It was found that the revealing residue causes cytotoxic effect on Allium cepa L., inhibits root growth and changes its quality. The DL50 (24h) found from the Survival Artemia salina test rate is 0.86% (v/v). The results show that improvements are essential in the management of waste from health facilities as well as the adoption of urgent actions that promote the reduction of radiological effluent generation, such as the replacement of the conventional image production for digital.