Unintentional poisoning occurs mainly in childhood due to ingestion of common household products. A decisive factor is the lack of knowledge concerning the potential toxicity of these products. A random study of 158 labels of cleaning products was conducted at the National Institute of Quality Control in Health--Brazil. Health hazard warnings, first aid in case of poisoning and storage instructions were evaluated to assess the quality of information provided to the consumer regarding the risks inherent in these products. Among these labels, 75% were considered inadequate since they did not provide all cautionary information necessary to avoid the health hazards associated with these products. First aid instructions in the case of inhalation were missing on more than 50% of labels studied and 47% did not recommend taking the label to a health professional in case of accident. Furthermore, the labels did not provide other important warnings such as "read before use" and "keep in original container': The results indicate that the labelling of cleaning products does not provide all safety information recommended for consumers.