Khan Usman, Nicell Jim A
Department of Civil Engineering & Applied Mechanics, McGill University, Montreal, Quebec, Canada.
PLoS One. 2014 Mar 26;9(3):e92630. doi: 10.1371/journal.pone.0092630. eCollection 2014.
This work explores the relationships between a user's choice of a given contraceptive option and the load of steroidal estrogens that can be associated with that choice. Family planning data for the USA served as a basis for the analysis. The results showed that collectively the use of contraception in the USA conservatively averts the release of approximately 4.8 tonnes of estradiol equivalents to the environment. 35% of the estrogenic load released over the course of all experienced pregnancies events and 34% the estrogenic load represented by all resultant legacies are a result of contraception failure and the non-use of contraception. A scenario analysis conducted to explore the impacts of discontinuing the use of ethinylestradiol-based oral contraceptives revealed that this would not only result in a 1.7-fold increase in the estrogenic loading of the users, but the users would also be expected to experience undesired family planning outcomes at a rate that is 3.3 times higher. Additional scenario analyses in which ethinylestradiol-based oral contraceptive users were modeled as having switched entirely to the use of male condoms, diaphragms or copper IUDs suggested that whether a higher or lower estrogenic load can be associated with the switching population depends on the typical failure rates of the options adopted following discontinuation. And, finally, it was estimated that, in the USA, at most 13% of the annual estrogenic load can be averted by fully meeting the contraceptive needs of the population. Therefore, while the issue of estrogen impacts on the environment cannot be addressed solely by meeting the population's contraceptive needs, a significant fraction of the estrogenic mass released to environment can be averted by improving the level with which their contraceptive needs are met.
这项研究探讨了用户对特定避孕方式的选择与该选择可能关联的甾体雌激素负荷之间的关系。美国的计划生育数据作为分析的基础。结果显示,在美国,避孕措施的使用总体上保守估计可避免约4.8吨雌二醇当量释放到环境中。在所有经历的怀孕事件过程中释放的雌激素负荷的35%以及所有由此产生的遗留物所代表的雌激素负荷的34%是避孕失败和未使用避孕措施的结果。一项旨在探究停止使用基于炔雌醇的口服避孕药的影响的情景分析表明,这不仅会导致使用者的雌激素负荷增加1.7倍,而且预计使用者经历意外计划生育结果的比率会高出3.3倍。其他情景分析将基于炔雌醇的口服避孕药使用者建模为完全转而使用男用避孕套、隔膜或铜宫内节育器,结果表明,与转换人群相关的雌激素负荷是高还是低取决于停用后所采用方法的典型失败率。最后,据估计,在美国,通过完全满足人群的避孕需求,最多可避免13%的年度雌激素负荷。因此,虽然雌激素对环境的影响问题不能仅通过满足人群的避孕需求来解决,但通过提高避孕需求的满足程度,可以避免相当一部分释放到环境中的雌激素量。