Total petroleum hydrocarbons concentration in the gastropod species patella coerulea l. from the western part of the libyan coast

Abstract EN

Biomonitoring programs of marine environment using biological species are widely used for pollution monitoring activities.

This study aims to assess the affect of patella sizes on the accumulation trend of total Petroleum hydrocarbons (PHs), as indication of the PHs bioaccumulation ability of Patella coerulea to be used as biomonitoring species for PHs monitoring and to assess the present levels of petroleum hydrocarbons contamination in the western part of the Libyan coast.

Samples of the limpet P.

coerulea specimens of different shell length were collected from three study sites namely: Abukamash; Zawra and Sabrata, located at the western coast of Libya.

The sampling was carried out at the mid of August 2001 from intertidal zone of the study sites.

P.

coerulea individuals were categorized in small and large sizes for each site based on the shell length.

Total PHs analysis was done by digesting the whole fresh flesh of the organism with 10M NaOH at 90oC for 3 hrs ,extracted with 5 ml of hexane for 2 min three times and centrifuging at 3000 rpm for 5 min.

The combined hexane extract was dried over anhydrous Na2SO4 and concentrated to 5ml using rotary evaporator.

Total PHs were measured by spectroflurometry at excitation wavelength 310 nm and Emission at 360 nm.

ROMPE crude oil used as a standard.

The results indicate higher concentration of total PHs in large sized specimens than in the small sized specimen, reflecting similar positive accumulation trend of PHs at the three sampling sites.

These similarities of the positive accumulation trends of size and concentration in the three sites indicate the ability of patella sp.

to accumulate petroleum hydrocarbons over various environmental conditions, suggesting the lack of regulation mechanism interference as size increases and P.

coerulea could be considered as biomonitoring species for PHs as it fulfill the ecological criteria of the selection of biomonitoring species.

The average values and ranges of total PHs in P.

coerulea regardless to the size from the study sites were: (111.337 ± 41.856?g/g wet wt.) for Abukamash site; (91.500 ± 34.198 ?g/g wet wt.) for Zwara site and (62.917 ± 25.956 ?g/g wet wt.) for Sabrata site.