Getting the Lead Out—with Sponges

For a few days last week, there was relief from the high temperatures, but the forecast for Sunday, May 14, in western Canada and the U.S. Pacific Northwest was for a "heat dome"—a high-pressure system that extends high into the atmosphere and traps warm air like a lid on a pot. Temperatures in Portland, Oregon, were predicted to be in the mid-90s and forecast to be in the high 80s in Seattle, Washington. Climate Central, a group of independent scientists, has already determined that the forecasted heat dome has the clear fingerprints of climate change.

The wildfires caused some oil and gas producers to shut down operations. However, as Clean Technica reports, there’s been little discussion in the media about the connection between climate change and the fires. Alberta is the largest producer of crude oil in Canada, and a study published last month suggested that greenhouse gas emissions from the province's oil sands may be significantly underestimated. In Alberta and neighboring Saskatchewan, the CBC reports that temperatures have warmed by about 1.9C since the mid-20th century, higher than the global rate.

Scientists at Northwestern University have developed a new sponge that they say can remove lead and other toxic metals and leave drinkable water behind. It was developed based upon previous research where a sponge was used to clean up oil spills. The newer sponge is coated with nanoparticles of manganese-doped goethite.

After cleaning contaminated tap water,  the researchers rinsed the sponge with a slightly acidic solution to recover the lead, which could then be used where it is needed, say, in batteries. The sponge could be reused with 90 percent of its effectiveness intact and could also capture other metals like cobalt.

The sponge is cheap and could be commercially available. The scientists say it can be an easy-to-use tool in home water filters or even in large-scale environmental remediation, for instance to remove metals from mine spills like the one in Colorado that turned the Animas River bright orange eight years ago.

The study was published in the journal ACS ES&T Water.

Researchers from the University of Hawaiʻi at Mānoa wanted to understand how cold-blooded scalloped hammerhead sharks (Sphyrna lewini) that can't produce their own body heat were able to hunt in deep waters—where temperatures are similar to those in Kodiak, Alaska (around 5°C/40°F)—without freezing to death.

Hammerheads and other fish use their gills as lungs to absorb dissolved oxygen in the water. But if the seawater they’re taking in is cold, they’ll get cold too. That is, unless they shut their gills to maintain body temperature, which is what the team discovered the scalloped hammerhead sharks were doing, by equipping three of them with devices that measured their muscle temperature, depth, body orientation, and activity levels.

They saw that the sharks’ muscles stayed warm throughout their journeys into the deep but suddenly cooled as they approached the surface, implying they were breathing again. The team found the hammerheads could shut their gills for 17 minutes on average, spending only four of those minutes feasting at the bottom.

The new insights could help to manage and conserve the sharks, which are increasingly vulnerable to changing ocean conditions—and more and more to human activities near the ocean floor, such as deep-sea mining.

This study was published in the journal Science.

Contrary to the impression multiple bites might leave, mosquitoes don’t live off people, they mostly feed on plant nectar. Female mosquitoes, however, will supplement with animal blood to produce eggs, so if you smell like a botanic garden after showering, you’re a one-stop shop.

Researchers at Virginia Tech explored the relationship between soaps and the insects by exposing four volunteers to Aedes aegypti mosquitoes which are vectors for numerous diseases. The scientists had participants lather up with Dial, Dove, Native, and Simple Truth soaps but also factored in the volunteers’ natural odors which can be influenced by everything from diet and lifestyle to products like laundry soap or deodorant. According to lead researcher Clément Vinauger, more than 60 percent of what is smelled after washing comes from soap rather than natural body odors.

Some volunteers were mosquito magnets from the get-go, but all soaps affected the extent of their appeal. Three of the four soaps increased mosquito attractiveness for the participants, while washing with the coconut-scented Native brand tended to repel the bugs. “That was very interesting for us because there is other evidence in the literature that elevating certain fatty acids, such as those found in coconut oil derivatives, could serve as a repellent for mosquitoes and other insects,” Vinauger said.

Before you rush out to buy coconut everything, know that the study was very small. That said, the research could lead to developing future repellents that are plant based so mosquitoes will just buzz off and leave us alone.

The study was published in iScience.