Arsenic Poisoning In Water
When we think of arsenic poisoning, we tend to imagine a bottle labeled with a skull and crossbones and all-caps DANGER and POISON. A 100 mg. arsenic dose (a 0.02-teaspoon droplet) is enough to kill a person within a few hours.
The 2013 New Yorker Murder by Poison began, “In early-nineteenth-century England, a good way to get rid of your husband was arsenic.”
So many British husbands suffered death-by-arsenic that in 1851 the House of Lords attempted to pass a law banning women from purchasing it.
But then, one might observe that men were also in on the arsenic action, arranging relatives’ demise to preserve their inheritances.
The New Yorker article details why arsenic poisoning was such an effective means of murder:
- “A medical examiner usually couldn’t tell whether the poison was involved because the symptoms—diarrhea, vomiting, abdominal pain—are much like those of other disorders.”
- “Nor could he necessarily place you at the murder scene. The dying typically took hours.”
- “Also, you could administer the poison gradually, a little bit every day.”
Then there’s this sinister line from a mid-1800s newspaper article: “Your friends and relations all smile kindly upon you: the meal… looks correct, but how can you possibly tell there is no arsenic in the curry?”
What a prophet that 19th-century reporter was! Fast forward 170 years and arsenic has become an all-too-common ingredient in our:
and most ominously, our drinking water!
Parts Per Billion, Just 11 Drops
The Food and Drug Administration limits water’s maximum arsenic level to 10 micrograms per liter – or ten parts per billion. To understand how concentrated ten parts per billion (ppb) is, let’s start smaller at parts-per-million…
Filling a 10-gallon aquarium with an eyedropper would require 1 million drops of water. Doing it eight hours a day, five days a week at the rate of 1 drop per second, you’d need seven weeks to fill the aquarium!
Now multiply that by 1,000 to get to the FDA’s parts-per-billion. Instead of a 10-gallon aquarium, imagine filling a 10,000-gallon swimming pool!
Because the task is so much more daunting, you’d work 12 hours per day, seven days per week, until you accomplish your mission – 63 years later!
Next, imagine for the last 10 seconds of the 63rd year, you substituted arsenic for the water in your eyedropper. Your swimming-pool water is now at the FDA’s limit for arsenic toxicity. Just 1 more drop of arsenic (11 ppb) would make swallowing it unsafe.
While the amount of arsenic most of us consume daily isn’t significant enough to cause acute (rapid) poisoning, long-term poisoning is another story.
Long-Term Arsenic Poisoning
Long-term arsenic poisoning from minuscule doses of arsenic is a 21st-century problem. This Public Health Statement from the CDC’s Agency for Toxic Substances and Disease Registry (ATSDR) reports:
“Arsenic cannot be destroyed in the environment. It can only change its form or become attached to or separated from particles. It may change its form by reacting with oxygen or other molecules present in air, water, or soil, or by the action of bacteria that live in soil or sediment.”
Many common arsenic compounds can dissolve in water. Thus, arsenic can get into lakes, rivers, or underground water by dissolving in rain or snow or through the discharge of industrial wastes. Some of the arsenic will stick to particles in the water or sediment on the bottom of lakes or rivers, and some will be carried along by the water.
Unfortunately, the ATSDR’s words came to catastrophic life in 2000, when the World Health Organization reported that Bangladesh had the “largest mass poisoning of a population in history because ground-water used for drinking has been contaminated with naturally occurring inorganic arsenic.”
Where did the arsenic originate?
In the 1970s, UNICEF began installing do-it-yourself tube wells to provide Bangladesh with clean water. The country’s polluted surface water was causing terrible outbreaks of cholera and diarrhea.
So UNICEF joined with the Bangladesh government to install millions of shallow, hand-pumped wells.
But the project went horribly wrong. The tube wells brought up the arsenic-tainted water, often registering 50 parts-per-billion, with worst-hit areas above 200 ppb. For the exposed Bangladesh people, that degree of toxicity could result in:
- abnormal heart rhythm
- heart disease
- partial paralysis
- small corns or warts on the palms, soles, and torso
- discoloration of skin
- thickening of skin
- numbness in hands and feet
- recurring diarrhea
But the news gets worse. The International Agency for Research on Cancer classifies arsenic as a Group 1 carcinogen, alongside asbestos, processed meat, and tobacco.
Arsenic poisoning is linked to increased risk of:
and bladder cancer.
Arsenic Poisoning Beyond Bangladesh
The arsenic poisoning problem reaches far beyond East Asia. In 2012, Researchers from UC Davis’ Department of Public Health Sciences estimated the exposure to multiple food-contaminates 959 participants, from preschoolers to older adults.
They found that in all 364 preschoolers and children, “Cancer benchmark levels were exceeded… for arsenic…” Figure 2 of their study showed arsenic risk ratios well above 100 for those groups.
The seriousness of the situation led the ATSDR to rank arsenic poisoning its top 2001 priority. They specifically expressed concern over severe soil contamination from an over-application of arsenic compounds in agricultural operations.
To rework a line from yesterday’s post, “Our fruits and veggies are no less toxic than the soil they grow in.”
In reality, we can’t avoid consuming arsenic. It’s in our food and water. So are there ways of minimizing our risk of poisoning?
More on this tomorrow.