Plant-based diets add to the wastewater phosphorus burden

Forber, Kirsty and Rothwell, Shane and Metson, Genevieve and Jarvie, Helen and Withers, Paul (2020) Plant-based diets add to the wastewater phosphorus burden. Environmental Research Letters, 15 (9). ISSN 1748-9326

Full text not available from this repository.


Global food production and current reliance on meat-based diets requires a large share of natural resource use and causes widespread environmental pollution including phosphorus (P). Transitions to less animal-intensive diets address a suite of sustainability goals, but their impact on society's wastewater P burden is unclear. Using the UK as our example, we explored historical diet changes between 1942 and 2016, and how shifting towards plant-based diets might impact the P burden entering wastewater treatment works (WWTW), and subsequent effluent P discharge to receiving water bodies. Average daily per capita P intake declined from its peak in 1963 (1599 mg P pp-1 d-1) to 1354 mg P pp-1 d-1 in 2016. Since 1942, the contribution of processed foods to total P consumption has increased from 21% to 52% in 2016, but consumption of total animal products has not changed significantly. Scenario analysis indicated that if individuals adopted a vegan diet or a low-meat ('EAT- Lancet') diet by 2050, the P burden entering WWTW increased by 17% and 35%, respectively relative to baseline conditions in 2050. A much lower P burden increase (6%) was obtained with a flexitarian diet. An increasing burden of P to WWTW threatens greater non-compliance with regulatory targets for P discharge to water, but also presents an opportunity to the wastewater industry to recycle P in the food chain, and reduce reliance on finite phosphate rock resources. Sustainable diets that reduce food system P demand pre-consumption could also provide a source of renewable fertilizers through enhanced P recovery post-consumption and should be further explored.

Item Type:
Journal Article
Journal or Publication Title:
Environmental Research Letters
Uncontrolled Keywords:
ID Code:
Deposited By:
Deposited On:
19 Aug 2020 11:25
Last Modified:
21 Sep 2023 02:58