Centre for Research In Bioscience, Department of Applied Sciences, University of the West of England, Coldharbour Lane, Frenchay, Bristol, BS16 1QY, United Kingdom.
Centre for Research In Bioscience, Department of Applied Sciences, University of the West of England, Coldharbour Lane, Frenchay, Bristol, BS16 1QY, United Kingdom.
J Environ Radioact. 2022 Apr;244-245:106828. doi: 10.1016/j.jenvrad.2022.106828. Epub 2022 Feb 3.
Global food supplies currently depend on producing inorganic P fertilisers from a finite reserve of rock phosphate (RP). P fertilisers are themselves significant pollutants but their production from RP also leaves a phosphogypsum (PG) by-product that is sufficiently radioactive that its reuse is restricted. PG is mostly accumulated in open 'stacks' that make up a significant proportion of all Technologically Enhanced Naturally-Occurring Radioactive Material (TENORM) waste. Using lower and upper estimates of current RP reserves, historic production, and Hubbert's logistic function-based 'peak theory', lower and upper boundaries for possible RP production were predicted to the year 2100. The 'low' boundary scenario had a production peak of c.350 Mt/a RP in c.2050 followed by a steep decline. The 'high' boundary scenario had a production peak of c.1200 Mt/a RP in about 2090. Future trends in P demand for food production were used to predict a possible, demand-driven, RP production scenario until 2100 which peaked at a demand of c.620 Mt/a RP and was within possible production boundaries. An RP:P ratio of 5.62:1 and PG:P fertiliser ratio of 4:1 was used to calculate that this predicted demand-driven scenario would ultimately produce nearly 350 Mt/a of PG and a cumulative total of c.30 Gt by 2100. Average PG activity concentrations of Ra (650 Bq/kg), Po (300 Bq/kg) and Th (100 Bq/kg) give a total of c.30 PBq radioactivity in this by-product. Humanity is faced with a phosphorus dilemma - if the low production scenario unfolds it threatens food security but if predicted demand for P is met from RP the environmental challenges arising from P fertiliser use will be profound and exacerbated by a significant radioactive waste challenge. The estimates reported here show that studies of environmental radioactivity have a role to play in debates about P resources and global food security.
目前，全球粮食供应依赖于从有限的磷矿资源（RP）中生产无机 P 肥料。P 肥料本身就是严重的污染物，但从 RP 生产 P 肥料还会产生磷石膏（PG）副产物，其放射性足以限制其再利用。PG 主要积累在开放式“堆”中，这些堆占所有技术增强型天然放射性材料（TENORM）废物的很大比例。根据当前 RP 储量、历史产量和哈伯特基于逻辑函数的“峰值理论”的高低估算，预测了 2100 年之前 RP 产量的上下限。“低”边界情景预计在 2050 年左右达到 RP 产量的峰值 350Mt/a，随后急剧下降。“高”边界情景预计在 2090 年左右达到 RP 产量的峰值 1200Mt/a。未来粮食生产对 P 的需求趋势被用来预测到 2100 年的可能的、需求驱动的 RP 生产情景，该情景的峰值需求为 620Mt/a 的 RP，处于可能的生产范围内。使用 5.62:1 的 RP:P 比例和 4:1 的 PG:P 肥料比例来计算，这个预测的需求驱动情景最终将产生近 350Mt/a 的 PG 和到 2100 年总计约 30 太吨的 PG。PG 中 Ra（650Bq/kg）、Po（300Bq/kg）和 Th（100Bq/kg）的平均活度浓度总计 30PBq 的放射性。人类面临着一个磷困境——如果低产量情景展开，它将威胁到粮食安全，但如果满足预测的对 RP 的 P 需求，P 肥料使用带来的环境挑战将是深远的，并因放射性废物的大量产生而加剧。这里报告的估计表明，环境放射性研究在关于 P 资源和全球粮食安全的辩论中发挥了作用。
