• The rate of zinc accumulation in the haemolymph is proportional to the dissolved zinc concentration to which the crab is exposed (and hence to the rate of uptake by the crab).

• Newly taken up labelled zinc is added sequentially over time to the zinc concentration already present in the haemolymph.

• Only at high ambient concentrations (1000 µg Zn l^-1) did incoming zinc replace bound zinc. However, even after a long term exposure, 60% of the zinc in the haemolymph remained too tightly bound to be replaced by incoming zinc.

• The half-life of zinc in the haemolymph is approximately 20.9 days (95% confidence limits 15.0 and 29.6 days) and is perhaps due to haemocyanin turnover.

• Following injection of zinc into the haemolymph it was found that the maximum concentration of zinc in the haemolymph (ca. 80 µg Zn ml^-1) was on average just more than double the normal concentration (34.7 µg Zn ml^-1) and remained below 100 µg Zn ml^-1 in all individual crabs.

To read more about my work check out.......

'The kinetics  of zinc and cadmium in the haemolymph of the shore crab, Carcinus maenas (L)'
Aquat. Toxicol. 40: 203-231 (1998).

'Haemocyanin, and the transport of zinc and cadmium in the haemolymph of the shore crab Carcinus maenas (L)'
Sci. Total Environ. 214: 133-152 (1998).

This research was carried out at Queen Mary, University of London, whilst in receipt of a NERC studentship.