Copper rates, and carcass dressing percentages. Chronic copper toxicity does not normally occur in humans because of transport systems that regulate absorption and excretion. Autosomal recessive mutations in copper transport proteins can disable these systems, leading to Wilson's disease with copper accumulation and cirrhosis of the liver in persons who have inherited two defective genes. Elevated copper levels have also been linked to worsening symptoms of Alzheimer's disease. In the US, the Occupational Safety and Health Administration (OSHA) has designated a permissible exposure limit (PEL) for copper dust and fumes in the workplace as a time-weighted average (TWA) of 1 mg/m.
Right hemisphere brain damage shifted to include right hemisphere damage (Brookshire, 2007). It is now well established that language and cognition can be seriously impaired by unilateral right hemisphere brain damage. Specific cognitive tests can help diagnose the existence of right hemisphere brain damage and differentiate symptoms from those of left hemisphere damage. Unlike the aphasias, caused by left hemisphere damage and generally resulting in focused language deficits, right hemisphere brain damage can result in a variety of diffuse deficits which complicate formal testing of this disorder (Brookshire, 2007). These formal tests assess areas such as understanding humor, metaphors, sarcasm, facial expression, and prosody.