Bioindicator Thais carinifera (mollusca, gastropoda): imposex response and consequences along the Pakistan coast during the period from 1993 to 2012

Abstract Endocrine mediated "imposex" phenomenon was investigated and recorded in the muricoid gastropod species Thais carinifera during the two decades from 1993 to 2012 at three (3) sites out of six (6) localities investigated along the Sindh and Balochistan coast, Pakistan. The VDS stages 1 to 4 were apparent in Thais carinifera. The intensity of imposex has remained comparatively low in the populations of harbours in close proximity to port Mohammad Bin-Qasim, namely; Old Korangi Fish Harbour (OKFH) and New Korangi Fish Harbour (NKFH) where shipping activities are sporadic as compared to those in Manora Channel and the adjoining Karachi Port area where intensive shipping activity is rather frequent. Target species found to be good bioindicators have shown a marked decrease over the prolonged study period. Investigations show that this decrease is solely due to globally imposed effective bans on tributyltin (TBT) based antifouling paints over the past decade

Organotin pollution from pleasure craft at Paraty, a tourist area of Southeastern Brazil: amelioration or interference?

Some organotin compounds, such as TBT, are endocrine disruptors and harm marine ecosystems. Even after the global ban on organotins, increasing imposex levels have been detected in Stramonita haemastoma analyzed in 2004 and 2011 in some locations at Paraty, a tourist area in southeastern Brazil. The results of this study indicate that particulate and dissolved organic carbon and xenoestrogens might be interfering in this syndrome's development, leading to underestimation of imposex evaluation. Chemical analysis of three mangrove swamp sediments in the area showed the presence of TBT (16.0 - 205.7 ng Sn g-1), DBT (10.1 - 16.4 ng Sn g-1) and MBT (10.1 - 10.2 ng Sn g-1) even at the reference sites. The concentrations of butyltins and the increased incidence of imposexat some stations indicate recent inputs of TBT in the study area due to its illegal use on small vessels