Humans rate water as to how safe it is to drink. The World Health Organization has defined what that means.

If we read their document we learn about the importance of a chloride safe balance. Because we still have lead pipes from the industrial era of the 19th and 20th century, we have realised, too late, that salt can corrode these pipes and thus cause leakages.

Chloride increases the electrical conductivity of water and thus increases its corrosivity. In metal pipes, chloride reacts with metal ions to form soluble salts (8), thus increasing levels of metals in drinking-water.

An example of negligence leading to serious health harm happened not too long ago in Flint, Michigan, USA.

In a research paper we find:

The chemistry of Flint River water was known to be highly corrosive to lead plumbing as well as iron pipe due to its high chloride content, which was about eight times higher than the chloride content in the DWSD water. 

But what of the fish in the Flint River?

In 2018, Michigan government produced this advice:

Michigan releases updated fish consumption guidelines relating to PFAS in Lake St. Clair, Flint River

FOR IMMEDIATE RELEASE: April 3, 2018

CONTACT: Lynn Sutfin, 517-241-2112

LANSING, Mich. – As part of the State of Michigan’s effort to address the emerging contaminant, perfluoroalkyl and polyfluoroalkyl substances (PFAS), the Michigan Department of Health and Human Services (MDHHS) has issued Eat Safe Fish guidelines for fish caught from Lake St. Clair and the Flint River in Genesee, Lapeer and Saginaw counties.

Fish in Lake St. Clair were tested as a result of the state’s PFAS effort, but guidelines have been set as a result of elevated levels of perfluorooctane sulfonate (PFOS), polychlorinated biphenyls (PCBs) and/or mercury. Guidelines have previously existed for Lake St. Clair relating to mercury, PCBs and dioxins. While there are three municipal drinking water intakes in Lake St. Clair, they were found to have detectable but very low levels of PFOS, well below the U.S. Environmental Protection Agency Lifetime Health Advisory Level of 70 parts per trillion.

Although Flint River fish consumption guidelines have been in place since 1993 for mercury and PCBs, PFOS was first included for fish in 2015 in the Flint River. Additional fish were collected from the Flint River in 2016 and analyzed in 2017 resulting in updated guidance. The Flint River is not a source of drinking water.

The Eat Safe Fish guidelines are set to be protective for everyone including children and pregnant and breastfeeding women. They are also set to be protective for people with existing health problems such as cancer or diabetes. Eat Safe Fish guidelines are provided as MI Servings. One MI Serving for adults is 6-8 ounces of fish (about the size of an adult’s hand). For children, one MI Serving is 2-4 ounces of fish (about the size of an adult’s palm).

The Limited MI Serving category is a special guideline used to describe fish that should only be eaten once or twice per year, at most, due to higher levels of chemicals. However, people who are under the age of 15; have health problems, such as cancer or diabetes; are planning on having children in the next several years; or are breastfeeding, should avoid eating all fish listed as Limited. The ^2x indicates the number of MI Servings can be doubled when fat is cleaned away and fish is cooked so more fat can drip away.

But the Flint River remains a favourite fishing spot it would seem.

The scandal of the negligence of the water treatment company causing a devastating impact on the local population seems to not have influenced the sport of fishing in the Flint River.

Yet, doctors found high levels of lead in the blood of children in 2015 and alerted the authorities. Perhaps that lead has already damaged the brains of those who continue to consume fish caught in the Flint River. They cannot have missed the intensity of global coverage of this infamous situation occurring in the United States of America.

This crisis should be a warning to all of us to assess the state of our drinking water and trace it back to the water sources from which we draw it. We must look at the infrastructure and give priority to the design and implementation of keeping our rivers safe. That is no small order, but we MUST put it to the top of our list.