For several days last week the mainstream media ran vivid reports on Guillemots and Razorbills coming ashore in Dorset and Devon with their feathers gummed up by a “mystery” substance. There were speculative statements that it could be Palm Oil, so with the wonders of internet search engines this led to a marked jump in hits on an earlier Natur Cymru blog about Palm Oil lumps being mistaken for ambergris. More useful however might have been checking out websites that deal with the transportation of the range of vegetable oils.
Some interesting experimental releases of such oils were done in France to plan for accidents. Palm Oil itself has a pour point (the temperature at which it melts) well above our winter sea temperatures. In the experimental releases it was observed to form a scatter of small lumps, so it was a rather unlikely cause of the problem. Several of the other vegetable oils have lower pour points, but they have been found to polymerise in seawater as decay sets in, rather than forming the sticky mousse emulsions that crude oils frequently do.
After a vessel carrying Sunflower Oil capsized off Anglesey the fresh oil spread as a very thin slick. When reaching the shore it gave rocks the appearance of having a thin coat of varnish. Being non-toxic it did not cause limpets to drop off and it soon vanished. More surprising to those of us then new to vegetable oil spills, it sometimes formed elastic sheets at the edge of some high shore rock pools and turned into thousands of little lumps like pieces of discarded chewing gum. As it went rancid an aroma of less salubrious chip shops hung over a few beaches.
A problem in the recent South Coast incident was that in the absence of a ship reporting damage to its tanks, or perhaps to a tank on a container ship, no one seemed to know what the mystery substance was for several days. This had consequences both for tracing the likely source and for anyone attempting to treat wildlife casualties. Seen from a distance just through media reports, the process of getting even preliminary scientific analyses to type the substance seemed to be rather slow. This delay just added extra hype to the “mystery” and the report that it was a refined mineral oil still seems rather non-specific.
There are lessons in this incident for authorities in Wales, particularly for those responsible after 1st April when Natural Resources Wales (NRW) goes live. It is to be hoped that NRW will have adequate capability to get analyses of strange substances affecting wildlife done promptly without having to prevail upon the goodwill of distant laboratories in England.
In practice samples need to be collected and processed for two rather different purposes. The first one, to find out what it might be, needs to be done quickly and can be based on whatever can be got to a suitable lab. However duplicate or triplicate samples may also need to be taken that have to be much more carefully stored and properly sealed as forensic specimens. There are already established protocols for handling oil samples in case of subsequent legal proceedings.
To end, here is a cautionary tale. Many years ago at sea we happened to pass a mile or two from an oil drilling platform where well testing was taking place. This involved flaring off the flow of oil. From a distance with binoculars, in addition to clouds of black smoke billowing up from the flare, “rain” was visible dropping from the flame. Later that day and at a distance down tide of the platform we came across a mass of small black and slightly crisp oil pellets on the sea surface. A sample was picked up and, in due course via HM Coastguard, was sent for analysis. The lab reported that it had the characteristics of heavy fuel oil. This delighted the PR side of the oil company, though the operational people did admit that there had been incomplete combustion and modifications were made to the flare. The fractions of the oil burnt as it was sprayed through a flare would have been similar to the fractions taken off during refining.
This article was written by Ivor Rees