and are corrosive. It should also be noted that reactive chemicals such as these may form highly toxic secondary
compounds. Where chlorine is used in an unventilated place, chlorine gas is generated as a by-product of its reaction
with organic compounds. Consequently, good working practices should be used to avoid creating situations where
the concentration in air may exceed safety limits.
Obsolete pesticides, stored in leaking drums or torn bags, can directly or indirectly affect the health of anyone who
comes into contact with them. During heavy rains, leaking pesticides can seep into the ground and contaminate
groundwaters. Poisoning can occur through direct contact with a pesticide formulation, inhalation of vapours,
drinking contaminated water or eating contaminated food. Other hazards may include the possibility of
spontaneous combustion if improperly stored, and contamination as a result of inadequate disposal, such as open
burning or indiscriminate burying.
Special care in handling genotoxic waste is essential. The severity of the hazards for health-care workers responsible
for the handling or disposal of genotoxic waste is governed by a combination of the substance toxicity itself and
the extent and duration of exposure. Exposure to genotoxic substances in health care may also occur during the
preparation of, or treatment with, particular drugs or chemicals. The main pathways of exposure are inhalation of
dust or aerosols, absorption through the skin, ingestion of food accidentally contaminated with cytotoxic drugs,
ingestion as a result of bad practice, such as mouth pipetting, or from waste items. Exposure may also occur
through contact with body fluids and secretions of patients undergoing chemotherapy.
The cytotoxicity of many antineoplastic drugs is cell-cycle specific, targeted on specific intracellular processes
such as DNA synthesis and mitosis. Other antineoplastics, such as alkylating agents, are not phase specific but