Certain industrial works represent a major source of toxicity and environmental pollution either to workers or to their surrounders. Most toxicities here are chronic especially for those exposed mainly and directly to fumes of melten metals. Biochemical screening for them may deserve great importance and attention. Liver represents a major site for such biochemical abnormalities. Groups of male healthy workers were selected and recruited from certain industrial locations ( melting units of different metals factories ). Liver enzymes mainly ( ALT, AST, ALP, AND ICDH ), heavy metals (Cu, Fe, Pb ), fibronectin and chondroitin sulphate were determined. Neither serum enzymes nor heavy metals levels recorded any changes. However, fibronectin and chondroitin sulphate demonstrated slgnificant increase. This represents early signs that may lead to cirrhotic changes later on. Recent data collected from animal studies, and liver histopathology have confirmed the above clinical findings. Routine liver function tests may not be sufficient to reflect the extent of toxicity. Other biochemical markers must be included to guarantee the correct assessment.