In April 2019 Ethical Consumer searched Bayer’s website, www.bayer.com, for information about its environmental reporting and practices. The Sustainability section of the website was viewed.

The company discussed health, agriculture, greenhouse gas emissions, waste, water, bees, sustainable agriculture and resource and energy efficiency. Overall the company was felt to have a reasonable understanding of its key environmental impacts.

In regard to environmental data, it presented emissions data, including direct and indirect green house gases; volatile organic compounds; total phosphorous in waste water; total nitrogen in waste water; total organic compounds. Bayer also presented waste data, including hazardous waste generated and landfilled. And resource use, including water use, primary energy consumption and secondary energy consumption.

A few environmental reduction targets were presented, including:
- Improvement of 10% in Group-wide energy efficiency by 2020. Reference year 2012: 3.50 Mwh/t
- Reduction of 20% in Group-wide specific greenhouse gas emissions by 2020. Reference year 2012: 0.98 t CO2/t
- By 2017 establishment of water management at all sites in water-scarce areas (35 sites)

No clear statement could be found that the data presented was independently verified.

Overall Bayer received Ethical Consumer’s middle rating for Environmental Reporting.

In May 2019 Ethical Consumer searched the Bayer website for the company's policy on the use of the hazardous chemicals parabens, triclosan and phthalates.

Some forms or uses of these chemicals are banned or restricted in the EU or the USA.

Triclosan is an antibacterial and is a suspected endocrine disruptor. Parabens are also endocrine disruptors and have been linked to breast cancer and are used as preservatives. Phthalates, usually DEP or DBP, are used in fragrances and are endocrine disruptors.

A strong policy on toxics would be no use of these chemicals or clear, dated targets for ending their use.
Nothing could be found that specifically mentioned these three chemicals.

Therefore the company received Ethical Consumer's worst rating on toxics.

On the 4 October 2016 Ethical Consumer viewed an article on the Guardian website called ‘Pesticide manufacturers' own tests reveal serious harm to honeybees’, published 22 September 2016. The article described how unpublished field trials by pesticide manufacturers had shown their products caused serious harm to honeybees at high levels; resulting in senior scientists calling for the companies to end the secrecy that hides their research.

The research was said to have been conducted by Syngenta and Bayer on their neonicotinoid insecticides. The research was said to have been submitted to the US Environmental Protection Agency and was obtained by Greenpeace after a freedom of information request.

The study showed how Bayer’s clothianidin seriously harmed bee colonies at high doses, but did not significantly effect bees below concentrations of 50 parts per billion (ppb) and 40ppb respectively. Such levels can sometimes be found in fields but concentrations are usually below 10ppb.

Ben Stewart from Greenpeace was quoted in the article stating: “If Bayer and Syngenta cared about the future of our pollinators, they would have made the findings public. Instead, they kept quiet about them for months and carried on downplaying nearly every study that questioned the safety of their products. It’s time for these companies to come clean about what they really know.”

It was reported on the website EcoWatch on 27th January 2016 that Seattle was the latest city to take out a lawsuit against Monsanto, alleging that Monsanto had known that chemicals, (polychlorinated biphenyls or PCBs) it had manufactured were polluting the environment and causing harm to people and wildlife.
The report said that though PCBs were banned for use in the United States in 1979, the toxic compound was still detected in the environment. PCBs had been known to have a negative effect on the human immune, reproductive, nervous and endocrine systems, and to cause cancer.
The suit was said to concern PCB contamination in 20,000 acres that drained into the lower Duwamish, which was a federal Superfund site (meaning it was so polluted that that the U.S. Environmental Protection Agency had to help with cleanup). It also concerned areas that drained to the East Waterway adjacent to Harbor Island, also a federal Superfund site.
The city was reportedly likely to seek millions of dollars from Monsanto to pay for the cleanup.
Under a consent decree issued by the Environmental Protection Agency (EPA) and the Washington Department of Ecology, Seattle already needed to spend at least $27?million to build a treatment plant to remove pollutants, including PCBs, from stormwater. However, as The Seattle Times pointed out, the plant would only cover a mere 1.25percent of the 20,000 acres that drain to the Lower Duwamish.

It had been reported that Monsanto allegedly knew that PCBs were toxic well before the 1979 ban but continued production of the profitable compound anyway. Think Progress reported: In a 1970 internal memo, agrochemical giant Monsanto alerted its development committee to a problem: Polychlorinated Biphenyls—known as PCBs—had been shown to be a highly toxic pollutant.