Introduction: According to Dz. U. nr 75 of 15 June 2002, building law does not allow visible signs of mold fungi in rooms used by people and imposes immediate renovation because of exposure to spores. Which being absorbed via airway and skin may be main sources of three forms: infection, allergy and toxicity. Mycotoxins get to the organism via digestive tract or airway with dust particles or food. Caused illnesses: Dry eye syndrome, eye socket necrosis, acute, persistent poisoning, impaired immunity, sinusitis, pharyngitis, bronchitis, pneumonia, asthma, air and skin allergy, headache, muscle aches, artralgia. Constant irritability, fatigue, insomnia, reduce concentration, memory disorder, even depression. In the digestive tract disturb metabolism, in extreme cases causing cirrhosis, even cancer; disorder pancreas, ovaries, prostate, and lead to sterility, kidney dysfunctions. Growth of fungi is connected with insufficient heating and ventilation. It is derivative socio-economic factors, hygiene level and health care. Purpose: Is presentation of the resulting threat from fungal spores and toxins exposure which are inside our houses, schools, hospitals, even our food based on available medical literature Conclusions: Mold Fungal toxins have an effect teratogenic, mutagenic and genotoxic inducing damaging many organs in experimental animals. Illnesses and deterioration of health are not connected with spores and toxins exposures. It may lead to wrong diagnosis and not eliminate fungi from the environment, what cause exacerbating symptoms. Fungal infection may be similar to other illneses as: tuberculosis, molluscum contagiosum, cryptococcosis, histoplasmosis what can delay proper diagnosis and significantlyreduce chances of survival. Species: Cladosporium, Alternaria, Aspergillus and Penicillium were found in high concentrations ta astmatic patients houses. It was connected with asthma symptoms deterioration in 36% to 48% cases.