Contact Lenses Add to Microplastic Pollution

Ever wonder what happens to disposable contact lenses when it's time to actually dispose of them?  Worn for as little as a day, their small size contributes to the danger they could eventually wind up polluting a lake, river or go out to sea as microplastic pollution.

After being flushed, the lenses float through the wastewater system to sewage treatment plants. Researchers tested 11 brands of contacts and found that they don't degrade during the treatment process but tear into smaller and smaller pieces.

The fragments are heavier than water, so they settle into the treated sewage sludge, which is often spread on land. The lenses can then make their way into rivers, lakes and the ocean through runoff.
Is sounds like a small problem, but an estimated 45 million people wear contact lenses in the US alone.  An estimated 20% of users flush their lenses resulting in up to 50,000 pounds of lenses getting flushed or rinsed down the drain.

Contact wearers should throw their lenses in the trash or recycle them.

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Can a Plant Fight Climate Change & Reduce Fertilizer Use?

The Azolla filiculoides fern— with leaves the size of gnats, is considered a wonder-plant that played a pivotal role in cooling our planet 50 million years ago. Among its many properties, the Azolla can capture CO2 and nitrogen from the air and has genes that provide insect resistance.

Some 50 million years ago, however, the planet was a much hotter place and Azolla grew as far north as the Arctic Ocean. Fossil records show that, fueled by abundant nitrogen and carbon dioxide, the fern formed thick mats across the entire ocean and crept onto the surrounding continents. Over the course of 1 million years, the plant pulled an estimated tens of trillions of tons of CO2 from the atmosphere, which scientists believe helped cool the planet to a climate more similar to what Earth has today.

Azolla filiculoides is a water fern and has been used as "green manure" in rice paddies in Asia for well over 1,000 years because of its symbiotic relationship with the cyanobacteria Nostoc azollae. The fern and the bacteria work together to capture nitrogen from the air and convert it into something the fern and other surrounded plants can use. This eliminates the need for nitrogen-added fertilizers.
Scientists are hopeful that they will be able to use genomes from the natural bio fertilizer of the plant to help lead to future sustainable agricultural practices.

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Soil Erosion and Water Pollution

The relationship between water quality and soil erosion cannot be overemphasized. Soil erosion and residue management, especially surface water runoff, influence water quality. A silt fence, sometimes called a filter fence, is a temporary sediment control barrier used on construction sites to protect water quality in nearby waterways from sediment in stormwater runoff.

The problem with silt fences is that they only filter sand and silt, clay and nutrients flow through the fences.  Placing a berm of compost on the low side of silt fences adds the capacity to filter out clays and nutrients. Compost contains both positive and negative charges that attract both positively and negatively charged elements and clays.

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Hunger for Sand Takes Toll on Endangered Species

Sand is used to make concrete and glass, it is an essential ingredient of nearly every modern highway, airport, dam, windowpane, and solar panel. Although desert sand is plentiful, its wind-tumbled particles are too smooth—and therefore not cohesive enough—for construction material. Instead, builders prize sand from quarries, coastlines, and riverbeds.

 

Sand is being dredged from inland freshwater lakes, altering lake ecology; as well as literally being hauled away by the shovel full from India’s Arabian Sea shoreline.  The sand removal is resulting in the loss of seagrasses and declines in Ganges River dolphin and terrapins, a critically endangered turtle.

Scientists are now tracing the collateral damage of sand removal.  Sediment plumes, stirred up by the dredging, block sunlight impeding photosynthesis of the nearby seagrass meadows.  These meadows nourish several species, including the dugong, which is also in decline.

Between 1994 and 2012, global cement production—a proxy for concrete use—tripled, from 1.37 billion to 3.7 billion tons, driven largely by Asian construction.  Land reclamation projects, too, have a rapacious hunger for sand. Singapore, for example, has expanded its land area by 22% using sand primarily from Malaysia, Cambodia, and Indonesia as fill. sand mining—on an industrial scale and by individual operators—greatly exceeds natural renewal rates.

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Drowning in Garbage

The World produces over 3.5 million tons to garbage a day, 10 times the amount from a century ago, but much less than the 11 million tons researchers estimate by the end of this century.  The world also produces over 300 million tons of plastic annually, of which only a small fraction is recycled.  

On average, a person in the United States or Western Europe uses about 220 pounds of plastic per year, according to the Worldwatch Institute, a research organization. The packaging industry, growing thanks to the rise of online stores and other factors, poses a huge challenge.

By 2050, there will be so much plastic floating in the ocean it will outweigh the fish, according to a study issued by the World Economic Forum. Scientists estimate that there are at least 5.25 trillion plastic particles — weighing nearly 270,000 tons — floating in the oceans right now.

Most waste in Africa, the United States and Asia ends up in dumps, many of which are already at capacity. Europe sends less of its waste to dumps or landfills and more to incinerators. While some of them are relatively clean, many are a threat to the environment and public health.

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