From: "howgate" <phowgate@rsc.co.uk>
To: <depsani@chilesat.net>; "seafood" <seafood@ucdavis.edu>
Sent: Friday, January 07, 2000 11:59 PM
Subject: Re: contaminación de alimentos con hidrocarburos

Estimados Colegas,

Estoy buscando información relativa a contaminación de peces con hidrocarburos (petróleo). Para esto necesito saber que hidorcarburos son producidos por los peces (biogénicos) y en que cantidad. Agradeceré cualquier información

Atentamente

Alejandra Alvarez

Sernapesca
Chile

Peter Howgate Wrote:

Alejandra

You ask about biogenic hydrocarbons in fish.

A wide range of hydrocarbons
are present in the aquatic environment from natural sources, that is without any contribution from petroleum. The biogenic hydrocarbons are predominately alkanes with high carbon numbers, typically more than 19. They are derived from plant and insect waxes and enter the aquatic environment directly from organisms, plant and animals, in the aquatic environment, or by run off from terrestrial sources, or by deposition from the atmosphere. The biogenic hydrocarbons are characterised by a predominance of molecules with odd-numbered carbons, whereas petroleum shows no preference for odd- or even-numbered carbons. Aromatic hydrocarbons are poorly represented in biogenic hydrocarbons fractions. The hydrocarbons in the aqueous phase are taken up by organisms and bioaccumulate up the trophic chain, hence will be found in fish, though not necessarily produced by the fish. For a review of the subject start with: Nevenzel, J.C., (1989), Biogenic hydrocarbons of marine organisms, in Marine biogenic lipids, fats and oils, R.G. Ackman, ed., CRC Press, Boca Raton, pp 3-71.

Peter Howgate