Considering the scale of the problem, the properties of HCB, and possible detrimental health effects from HCB, including hepatic porphyria, altered thyroid hormones, and tumorigenicity, degradation methods for this highly persistent compound are discussed in the literature, but most research has focused on environmental residues of this pesticide in the air, water, soil, and wastewater [51]. The gene discussed is TG; the disease is hepatic porphyria.