Getty Images
Getty Images

What Ever Happened to Acid Rain?

Getty Images
Getty Images

Back when I was a kid, life was pretty simple. Saturday morning cartoons were awesome, Ecto Cooler was abundant and the Soviet Union collapsed before they could drop any nukes on us. I couldn’t watch the news, or even my cartoons, though, without being reminded that there were other problems out there. Namely, a hole in the ozone layer and acid rain falling from the sky (which, in my mind at the time, meant the world was going to start melting).

Scary and omnipresent as they were then, these two environmental disasters don’t make headlines like they used to. Ethan checked in on the ozone layer earlier this year, but what became of acid rain? We fixed it. Kind of.

What is Acid Rain?

Acid rain, according to the Environmental Protection Agency, is what you get when chemical emissions from man-made and natural sources (primarily sulfur dioxide (SO2) and nitrogen oxides (NOx) from fossil fuel combustion) go up into the atmosphere and react with water, oxygen, and other chemicals to form acidic compounds and then come back town as acidic rain, snow, sleet, or fog.

To my relief, the stuff doesn’t melt buildings or people instantly, but it can corrode certain building materials, and fine sulfate and nitrate particles can be inhaled, causing inflammation and damage to tissues in the circulatory and respiratory systems. It also wreaks havoc on plants and animals, turning water too toxic for fish and tweaking soil chemistry so it can’t support plant life.

Acid rain started to disappear from the public mind in the 1990s, when the government strengthened environmental regulations. A 1990 amendment to the Clean Air Act required reductions in the types of emissions that led to acid rain, by way of cap-and-trade programs like the EPA’s  Clean Air Interstate Rule (CAIR) and the Acid Rain Program (ARP) and technology like smokestack “scrubbers” and low NOx burners. Emissions began to fall dramatically and are now millions of tons lower than they were in the late 80s and early 90s.

That’s great for us, and acid rain is long gone from the plot lines of American cartoons, but it’s still a problem elsewhere in the world. In some countries, particularly China, lax regulation and expanding industrialization and fossil fuel use led to an increase in acid rain-forming emissions and instances of acid rain in the early 2000s. More recently, the Chinese have begun to turn things around by shutting down smaller, inefficient coal power plants and retrofitting larger ones with sulfur dioxide scrubbers and emissions-monitoring equipment.

nextArticle.image_alt|e
iStock
arrow
Big Questions
What Do Morticians Do With the Blood They Take Out of Dead Bodies?
iStock
iStock

Zoe-Anne Barcellos:

The blood goes down the sink drain, into the sewer system.

I am not a mortician, but I work for a medical examiner/coroner. During an autopsy, most blood is drained from the decedent. This is not on purpose, but a result of gravity. Later a mortician may or may not embalm, depending on the wishes of the family.

Autopsies are done on a table that has a drain at one end; this drain is placed over a sink—a regular sink, with a garbage disposal in it. The blood and bodily fluids just drain down the table, into the sink, and down the drain. This goes into the sewer, like every other sink and toilet, and (usually) goes to a water treatment plant.

You may be thinking that this is biohazardous waste and needs to be treated differently. [If] we can’t put oil, or chemicals (like formalin) down the drains due to regulations, why is blood not treated similarly? I would assume because it is effectively handled by the water treatment plants. If it wasn’t, I am sure the regulations would be changed.

Now any items that are soiled with blood—those cannot be thrown away in the regular trash. Most clothing worn by the decedent is either retained for evidence or released with the decedent to the funeral home—even if they were bloody.

But any gauze, medical tubing, papers, etc. that have blood or bodily fluids on them must be thrown away into a biohazardous trash. These are lined with bright red trash liners, and these are placed in a specially marked box and taped closed. These boxes are stacked up in the garage until they are picked up by a specialty garbage company. I am not sure, but I am pretty sure they are incinerated.

Additionally anything sharp or pointy—like needles, scalpels, etc.—must go into a rigid “sharps” container. When they are 2/3 full we just toss these into one of the biotrash containers.

The biotrash is treated differently, as, if it went to a landfill, then the blood (and therefore the bloodborne pathogens like Hepatitis and HIV) could be exposed to people or animals. Rain could wash it into untreated water systems.

This post originally appeared on Quora. Click here to view.

nextArticle.image_alt|e
iStock
arrow
Big Questions
Why Does Asparagus Make Your Pee Smell Funny?
iStock
iStock

The asparagus has a long and storied history. It was mentioned in the myths and the scholarly writings of ancient Greece, and its cultivation was the subject of a detailed lesson in Cato the Elder's treatise, On Agriculture. But it wasn't until the turn of the 18th century that discussion of the link between asparagus and odorous urine emerged. In 1731, John Arbuthnot, physician to Queen Anne, noted in a book about food that asparagus "affects the urine with a foetid smell ... and therefore have been suspected by some physicians as not friendly to the kidneys." Benjamin Franklin also noticed that eating asparagus "shall give our urine a disagreeable odor."

Since then, there has been debate over what is responsible for the stinky pee phenomenon. Polish chemist and doctor Marceli Nencki identified a compound called methanethiol as the cause in 1891, after a study that involved four men eating about three and a half pounds of asparagus apiece. In 1975, Robert H. White, a chemist at the University of California at San Diego, used gas chromatography to pin down several compounds known as S-methyl thioesters as the culprits. Other researchers have blamed various "sulfur-containing compounds" and, simply, "metabolites."

More recently, a study demonstrated that asparagusic acid taken orally by subjects known to produce stinky asparagus pee produced odorous urine, which contained the same volatile compounds found in their asparagus-induced odorous urine. Other subjects, who normally didn't experience asparagus-induced odorous urine, likewise were spared stinky pee after taking asparagusic acid.

The researchers concluded that asparagusic acid and its derivatives are the precursors of urinary odor (compared, in different scientific papers, to the smell of "rotten cabbage," "boiling cabbage" and "vegetable soup"). The various compounds that contribute to the distinct smell—and were sometimes blamed as the sole cause in the past—are metabolized from asparagusic acid.

Exactly how these compounds are produced as we digest asparagus remains unclear, so let's turn to an equally compelling, but more answerable question:

WHY DOESN'T ASPARAGUS MAKE YOUR PEE SMELL FUNNY?

Remember when I said that some people don't produce stinky asparagus pee? Several studies have shown that only some of us experience stinky pee (ranging from 20 to 40 percent of the subjects taking part in the study, depending on which paper you read), while the majority have never had the pleasure.

For a while, the world was divided into those whose pee stank after eating asparagus and those whose didn't. Then in 1980, a study complicated matters: Subjects whose pee stank sniffed the urine of subjects whose pee didn't. Guess what? The pee stank. It turns out we're not only divided by the ability to produce odorous asparagus pee, but the ability to smell it.

An anosmia—an inability to perceive a smell—keeps certain people from smelling the compounds that make up even the most offensive asparagus pee, and like the stinky pee non-producers, they're in the majority.

Producing and perceiving asparagus pee don't go hand-in-hand, either. The 1980 study found that some people who don't produce stinky pee could detect the rotten cabbage smell in another person's urine. On the flip side, some stink producers aren't able to pick up the scent in their own urine or the urine of others.

Have you got a Big Question you'd like us to answer? If so, let us know by emailing us at bigquestions@mentalfloss.com.

SECTIONS

arrow
LIVE SMARTER
More from mental floss studios