We have no idea how much damage plastic pollution causes

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Pengarah Kanan dan Penganalisis Utama

I’m writing a lot about plastic waste recently, as we’ve been approaching the deadline for the UN’s binding instrument on plastic waste. Corporations are missing the point by mostly focusing their efforts and concerns around the recycling portions of the instrument when a lot of the instrument — maybe even most of it when you consider what’s likely to be adopted — is focused on plastic and microplastic pollution. But the challenge for regulators, industry, and me is that we really have no idea at all what the true cost of plastic pollution is. 

How much could production, cleanup, environmental impacts, and health impacts cost? There are pretty astonishing estimates out there: The World Wildlife Fund (WWF), for example, reports lifecycle costs as USD 370/tonne for production, USD 170/tonne for greenhouse gases, and USD 32/tonne for waste management, which are all quite reasonable. Then, it includes a USD 3,142/tonne cost for marine ecosystem services. Wow! Some shrimp are clearly getting rich off all this plastic waste. Now, the idea is that our oceans provide a huge amount of value to humans — some 4% of all food, supporting the ecosystem that produces most other food, regulating global temperatures, waterskiing, etc. If you damage that ecosystem, you damage the ability of the ocean to produce those services, which has a cost. That’s all very true — but how did the WWF get to the USD 3,142 number? The short version is: someone just made it up. 

In long, WWF cites a paper by Beaumont et al. on the damage to marine ecosystem services, which estimates a 1%–5% decrease in marine services would result in a USD 500 billion to USD 2 trillion loss in value, which it then divides across the volume of plastics entering the ocean to get costs between USD 3,300/tonne to USD 33,000/tonne. The problem is that according to the paper, that 1%–5% number is more or less plucked out of thin air: “In light of this evidence [of negative impacts from plastics], it is considered reasonable to postulate a 1%–5% reduction in marine ecosystem service delivery as a result of the stock of marine plastic in the oceans in 2011.” The paper points out that this is conservative because changes in land use have decreased terrestrial environmental services by 11% to 28%, but land use is not the same as pollution! That really doesn’t make any sense as a comparison. There’s really no basis for this leap; as the paper itself points out: “Based on available research it is not yet possible to accurately quantify the decline in annual ecosystem service delivery related to marine plastic.” This admitted conjecture is the entire basis for the WWF’s claims that plastic lifecycle costs are 10× the production costs. The WWF itself doesn’t even bother trying to quantify the other costs of plastic pollution, that is, the health impacts of microplastics. 

I’m not trying to make the case that plastic pollution isn’t a big deal or that ecosystem services don’t matter. It is, and they do. The problem is that we really have no idea how much damage plastic pollution causes. These dodgy estimates are driving global regulation — the UN cites the Baumont paper in its justification for the binding instrument! But it’s going to be very difficult to develop useful regulations, with all the tradeoffs that entails, when we have no idea what the costs are. This is very different from climate change, where the (very rigorous) estimates of damage, the pricing from mechanisms like the European Emissions Trading Scheme, and the price of sequestering a metric ton of carbon using carbon capture and sequestration are all roughly converging. These costs and prices give us confidence to make long-term planning decisions — for example, we can recognize that direct air capture is likely to be way out of step with the cost of carbon emissions for decades to come. How can we evaluate approaches to reduce plastic pollution in the current environment? Consider a packaging manager trying to decide between two designs: One isn’t recyclable but has very low emissions (like a plastic film), while the other is recyclable but has more mass and thus more emissions. How can you evaluate the tradeoffs? You can’t. Companies can try to develop their own costing models here, but that’s a pretty incomplete solution — both because it’s difficult to do and there’s no guarantee your estimates will line up with those of other groups. The other bad news is that the financing elements of the UN binding instrument are going to be extremely difficult to price and enforce, likely stymieing any substantial cleanup efforts for the foreseeable future. I do think we’ll put a firm(-ish) number on the damage eventually, but it could be years — decades even, if carbon emissions are any example — before we have a clear picture. Companies should be proactive in eliminating sources of plastic leakage from their value chains, lest they end up in a repeat of the PFAS liability situation

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