TEN ENVIRONMENTAL REPORTS

March 2025

1.Urban rodent numbers soar as the climate heats

Jonathan L. Richardson, et l., “Increasing rat numbers in cities are linked to climate warming, urbanization, and human population,” Science Advances (31 Jan 2025). bit.ly/40YFkhy

Abstract:

Urban rats are commensal pests that thrive in cities by exploiting the resources accompanying large human populations. Identifying long-term trends in rat numbers and how they are shaped by environmental changes is critical for understanding their ecology, and projecting future vulnerabilities and mitigation needs. Here, we use public complaint and inspection data from 16 cities around the world to estimate trends in rat populations. Eleven of 16 cities (69%) had significant increasing trends in rat numbers, including Washington D.C., New York, and Amsterdam. Just three cities experienced declines. Cities experiencing greater temperature increases over time saw larger increases in rats. Cities with more dense human populations and more urbanization also saw larger increases in rats. Warming temperatures and more people living in cities may be expanding the seasonal activity periods and food availability for urban rats. Cities will have to integrate the biological impacts of these variables into future management strategies.

See also, Phoebe Weston and Leyland Cecco, “ ‘Perfect rat storm’: urban rodent numbers soar as the climate heats, study finds,” The Guardian (31 Jan 2025). bit.ly/4guejHb

2. Water chlorination and risks for bladder and colorectal cancer

Emilie Helte, et al., “Exposure to Drinking Water Trihalomethanes and Risk of Cancer: A Systematic Review of the Epidemiologic Evidence and Dose-Response Meta-Analysis,” Environ Health Perspect (Jan 2025). bit.ly/410I2Ca

Abstract

Background: Chlorination is a widespread method for drinking water disinfection that has the drawback of introducing potentially carcinogenic chemical by-products to drinking water.

Objective: We systematically evaluated the epidemiologic evidence of exposure to trihalomethane (THM) disinfection by-products and risk of cancer…

Results: The literature search resulted in 2,022 records, of which 29 publications assessing 14 different cancers were eligible for inclusion. Summary relative risks (RRs) were estimated for bladder cancer and colorectal cancer based on 5,860 and 9,262 cases and 84,371 and 90,272 participants, respectively. The summary RR of bladder cancer for the highest exposed compared with the lowest was 1.33 (95% CI: 1.04, 1.71), and in the dose-response analysis, RRs were statistically significant above THM concentrations of 41μg/L

For colorectal cancer, the summary RR was 1.15 (95% CI: 1.07, 1.24).

Conclusion: According to the World Cancer Research Fund criteria, we found limited-suggestive evidence that THM in drinking water increases the risk of bladder and colorectal cancer at levels below current regulatory limits in the US and EU, indicating that these fail to protect against cancer in the general population. doi.org/10.1289/EHP14505.

See also, Tom Perkins, “Water chlorination levels in US and EU likely increase cancer risk, study finds,” The Guardian (17 Feb 2025).  bit.ly/4hLgc44 via @guardian

3. How reintroducing wolves to Highlands could help native woodlands

D. V. Spracklen, et al., “Wolf reintroduction to Scotland could support substantial native woodland expansion and associated carbon sequestration,” AER Ecological Solutions and Evidence (16 Feb 2025). bit.ly/411zISC

See also PA Media, “Reintroducing wolves to Highlands could help native woodlands, says study,” The Guardian (17 Feb 2025). bit.ly/4b6abfz

“Reintroducing wolves in the Scottish Highlands could lead to an expansion of native woodland, which could take in and store 1m tonnes of carbon dioxide a year, researchers have suggested.

A study led by researchers at the University of Leeds said that reintroducing the species into the Cairngorms, as well as the south-west, north-west and central Highlands could help curb the problem of red deer eating tree saplings, which stops natural woodland regeneration.

The scientists estimated that if wolves were reintroduced, a population of about 167 of the animals would thrive, which they said would be enough to reduce red deer populations to a level that would allow trees to regenerate naturally.”

4.  Brake pad dust can be more toxic than exhaust emissions

James G.H. Parkin, et al., “Copper-enriched automotive brake wear particles perturb human alveolar cellular homeostasis,” Particle and Fibre Toxicology (13 Feb 2025). bit.ly/3EE8n18

See also, Rachel Keenan, “Brake pad dust can be more toxic than exhaust emissions, study says,” The Guardian (14 Feb 2025).  bit.ly/4gIxAoz via @guardian

“Microscopic particles emitted from brake pads can be more toxic than those emitted in diesel vehicle exhaust, a study has found.

This research shows that even with a move to electric vehicles, pollution from cars may not be able to be eradicated.

The researchers found that a higher concentration of copper in some commonly used brake pads was associated with increased harmful effects on sensitive cells from people’s lungs, as a result of particles being breathed in.

Exposure to pollution generated by cars, vans and lorries has been previously been linked to an increased risk of lung and heart disease. While past attention has mainly concentrated on exhaust emissions, particles are also released into the air from tyre, road and brake pad wear.”

5. Global Importance of Peatlands and the Extent of Their Protection

Kemen J. Austin, “Mismatch Between Global Importance of Peatlands and the Extent of Their Protection,” Conservation Letters(12 Feb 2025).  bit.ly/3CYwwPB

Global peatlands store more carbon than all the world’s forests biomass on just 3% of the planet’s land surface. Failure to address mounting threats to peatland ecosystems will jeopardize critical climate targets and exacerbate biodiversity loss. Our analysis reveals that 17% of peatlands are protected globally—substantially less than many other high-value ecosystems. Just 11% percent of boreal and 27% of temperate and tropical peatlands are protected, while Indigenous peoples’ lands encompass at least another one-quarter of peatlands globally. Peatlands in protected areas and Indigenous peoples’ lands generally face lower human pressure than outside those areas. Yet, almost half of temperate and tropical peatlands in protected areas still experience medium to high human pressure. Country submissions of Nationally Determined Contributions under the Paris Agreement and National Biodiversity Strategy and Action Plans under the Kunming–Montreal Global Biodiversity Framework could help catalyze actions and secure funding for peatland conservation, including support for the Indigenous stewardship that is critical to protect many of the world’s highest priority peatland areas.

6.  Pennsylvania sues Trump and restores $2.1 billion in funding

Jon Hurdle, “Trump Administration Restores $2.1 billion in Funding to Pennsylvania After State’s Lawsuit,” Inside Climate News (25 Feb 2025).  bit.ly/4kvzwUL

Federal funding to Pennsylvania for climate-related and other programs will be restored, Gov. Josh Shapiro said, reversing a Trump administration freeze after lawsuits by Pennsylvania and almost two dozen other states.

Shapiro sued the Trump administration Feb. 13 in federal court over the funding freeze, arguing that it had illegally halted or subjected to an unspecified review $2.1 billion in federal funds that had been committed to Pennsylvania after being approved by Congress.

7.  Warming climate undermines Trump’s Greenland land grab

Kiley Price, “Climate Change Could Thwart Trump’s Efforts to Occupy Greenland,” InsideClimate News (25 Feb 2025). bit.ly/3XkRa3j

President Donald Trump is pushing for a Greenland land grab. But warming temperatures could disrupt development in the region.

The world’s largest island is known for its vast ice sheet, sprawling fjords and abundance of wildlife—from polar bears to narwhals.

It’s also one of the latest targets in President Donald Trump’s bid for U.S. energy and military expansion. Since his first term, Trump has talked of securing Greenland for its critical minerals, untapped oil reserves, opportunities for military positioning and central location in the international shipping network, particularly as melting sea ice opens up new trade routes. Now, he is pushing for a Greenland land grab with renewed vigor, offering to purchase the island from Denmark or even potentially take it by force.

But the same warming temperatures that may transform the island into a trading hotspot are making it more inhospitable to development, research shows. Thawing permafrost and ice triggers landslides along jagged fjords and destabilizes the landscapes that infrastructure would need to lie on top of, while loose sea ice makes passing through Greenland’s waters a perilous journey.

8. Christian Democrats win in Germany but are limited over changes to energy policies

The center-right Christian Democratic Union won the general election on Sunday with promises to restrict immigration, reduce taxes and make energy more affordable. The party, whose leader, Friedrich Merz, is poised to become the nation’s next chancellor, also campaigned on a willingness to reverse the country’s phaseout of nuclear power.

The Christian Democrats’s vote share of 28.5 percent fell short of a strong win, which limits its ability to make substantial changes. Germany has been a global leader in making a transition away from fossil fuels and a key player in international climate treaties.

“The story of tonight is that we have a government that has a fresh mandate but a weak mandate, but goes into a situation where they actually need a strong mandate,” Jan Techau, director of Europe for the Eurasia Group, said on the German television network DW News.

9. Trump’s firing of experts might backfire by reducing his ability to defend weakening rules

Dharna Noor, “Trump may rue firing experts when environmental rollbacks land in court,” The Guardian (26 Feb 2025). bit.ly/4kcWAXX

Amid spending freezes and policy rollbacks from Donald Trump, environmental advocacy groups are gearing up for a long series of legal showdowns with the administration.

The experience of suing Trump during his first term has left the movement better prepared, but the court battles will still be daunting, with the administration appearing to test the nation’s legal boundaries in an effort to consolidate power under the executive branch.

Trump’s firing of experts might backfire by reducing his ability to defend weakening rules, advocates say, though there are also fears, stirred by Trump and Vice-President JD Vance, that the administration will not obey court rulings.

10.  The Amoc is becoming unstable and approaching a tipping point

Damian Carrington, “Total collapse of vital Atlantic currents unlikely this century, study finds,” The Guardian (26 Feb 2025). bit.ly/41fHqIQ

Vital Atlantic Ocean currents are unlikely to completely collapse this century, according to a study, but scientists say a severe weakening remains probable and would still have disastrous impacts on billions of people.

The Atlantic meridional overturning circulation (Amoc) is a system of currents that plays a crucial role in the global climate. The climate crisis is weakening the complex system, but determining if and when it will collapse is difficult.

Studies based on ocean measurements indicate that the Amoc is becoming unstable and approaching a tipping point, beyond which a collapse will be unstoppable. They have suggested this would happen this century, but there are only 20 years of direct measurements and data inferred from earlier times bring large uncertainties.