Without a coherent approach to ocean pollution, shipping may find itself able to address either biofouling or microplastics, but not both
Without a coherent approach to ocean pollution, shipping may find itself able to address either biofouling or microplastics, but not both.
A study released by IMO last month reviews evidence that hull cleaning and marine coatings could be factors in microplastic pollution to oceans. It follows research by the International Union for the Conservation of Nature in 2017, which estimated that marine coatings represent 3.7% of microplastic pollution to the world’s oceans.
IMO requests more research before deciding whether intervention is needed. It recommends at least three studies be carried out: an initial look at different paint types to assess microplastics pollution both in normal use and from cleaning; research into whether the size of plastic particles is relevant to biological and environmental impact; and an assessment of the commercial impact on the shipping maintenance industry of potential control measures.
There is another factor to consider; the IMO’s commitment to reduce biofouling. This is embodied on one hand by the implementation of the 2004 Ballast Water Management Convention, and on the other by the 2011 Biofouling Guidelines. Those guidelines recommend the use of hull coatings and cleaning to control invasive species. Any measure to reduce the microplastics impact of hull coatings must be considered in the light of measures already recommended for reducing biofouling.
Two cautionary tales should stay in regulators’ minds. First is that this is not the only time that shipping has found itself with opposing environmental interests. IMO’s NOx emission limits often demand a trade-off in fuel consumption when exhaust treatment is involved. Likewise sulphur emissions solutions except LNG (itself far from perfect) also have a carbon cost, whether it is the energy needed to run scrubbers on ships or to produce compliant fuel at refineries.
Shipowners have often lamented the need to balance these competing interests. What was needed then was an approach to airborne emissions that recognised and prioritised these opposing forces. Something similar may be needed for waterborne pollution, namely microplastics and biofouling.
The second tale is that of the now-banned paint ingredient tributylin (TBT). IMO acknowledged its toxic (and in places devastating) impact on marine life in 1989, but it was not until 2008 that the convention banning it entered into force. How much credibility did IMO lose with observers outside shipping in those 19 years?
If further research does suggest that regulation on microplastics is needed, regulators cannot make the same mistakes. Regulation must be both coherent with existing requirements and implemented at a reasonable pace. Like all balancing acts, it will be no easy task. But identifying potential concerns at this early stage should allow for a sure-footed response.