Toxic chemicals and climate change work together to harm fertility across species

In a recent review published in NPJ Emerging Contaminants, researchers examine how toxic chemicals can reduce fertility in both humans and wildlife, and how these effects are worsened by climate change.

In short:

• Animals - including insects, fish, reptiles, birds, humans, and other mammals - are constantly simultaneously exposed to synthetic chemicals and the impacts of climate change, including rising temperatures.
• Both of these stressors can harm fertility, and many of the impacts found are similar across species, such as effects on sperm and eggs.
• The stress caused by these exposures also impacts overall health, harming animals’ ability to adapt to a changing environment and worsening global biodiversity loss.

Key quote:

“To build a sustainable future, we must recognize that chemicals, once released, don’t simply disappear. Instead, they contribute to the larger issue of driving humanity towards the exceedance of planetary boundaries when considered in combination with climate change and other planetary-level impacts.”

Why this matters:

While climate change and toxic endocrine disrupting chemicals (EDCs) are both individually well-established as health threats, few studies have examined the implications of the widespread simultaneous exposure experienced by humans and wildlife. Many EDCs can also impact health across multiple generations, meaning their harm continues long after the original exposure. To better tackle the issue of EDCs, the authors of this study emphasize the need for strong regulations that address chemicals by class, rather than individually.

Related EHN coverage:

• Declining PFAS levels in seabird eggs reflect impact of regulatory action
• Op-ed: A stalled global plastic treaty threatens our future fertility (written by two of the lead authors of the above study)

More resources:

• ChemTrust: Wildlife and the environment – Endocrine disruptors
• Stockholm Resilience Center: Planetary Boundaries: The safe operating space for humanity

Brander, S. et al. (2026). Impacts of environmental stressors on fertility and fecundity across taxa, with implications for planetary health. NPJ Emerging Contaminants.