The image shows an asbestos body i.e. an asbestos fibre which has been coated by ferruginous protein during its residence within the human lung. Various smaller scale events occur such as leaks from road tankers, or fires in warehouses and factories. Special local environmental exposures can arise for example in communities exposed to drifting pesticide sprays containing say, organophosphates. Some natural phenomena such as volcanic eruptions can present serious risks to health. Fortunately they are rare but can be catastrophic.
Water can be an important source of chemical hazards.
It can leach lead from pipes especially if the water is soft. Other adverse effects can arise from chemicals added to the water. Fluoride added to water reduces the risks of caries but can also have unwanted effects such as mottling of the teeth. Although pesticides can and do leach into water, there is no evidence that the current standards for water quality are inadequate in this respect, but most standards are based on evidence other than human epidemiology which in this context is extremely difficult to conduct. Beyond the point of supply further problems in drinking water quality may result.