Why do people poison themselves with lead? Earth scientists explain what to look for


The Biden administration released a plan to speed up the removal of lead water pipes and lead paint from American homes. As a geochemist and environmental health researcher who has studied the heartbreaking impacts of lead poisoning in children for decades, I’m happy to see high-level attention being given to this silent killer, which disproportionately affects poor communities of color.

Lead poisoning in children has declined dramatically in the United States over the past 50 years. Much of this is due to the phase-out of leaded gasoline in the 1980s and the ban on most lead-based paints.

But the United States Environmental Protection Agency estimates that up to 10 million homes and 400,000 schools and daycares have hookups or other devices that contain lead. These pipes are time bombs that can leach toxic lead into drinking water if they corrode. As long as they remain in service, children and families are vulnerable.

The same is true of lead paint, which is still present in many homes built before the use of lead paint by consumers was banned in 1978. Because it tastes sweet, children sometimes chew on paint chips or painted wood.

The Biden administration will spend $ 15 billion from the recently enacted infrastructure bill to replace service lines, valves and lead fixtures over the next five years and is seeking additional funds under the Build Act. Back Better Act underway to reduce lead-related risks in public housing and lower income communities. I consider this a key priority since black children and children living in poverty have average blood lead levels that are 13 percent higher than the national average.

Lead poisoning causes permanent damage

Lead poisoning is a major public health problem because lead has permanent impacts on the brain, especially in children. Young brains are still actively forming the amazing network of neurons that make up their material.

Neurons are designed to use calcium, the most abundant mineral in the human body, as a transmitter to transmit signals rapidly. Lead molecules are very similar to calcium molecules, so if they are present in a child’s body, they can enter the brain, interfere with the development of neurons, and cause permanent neural damage.

Children with lead poisoning have lower IQs, poor memory, high rates of attention deficit disorder, and poor impulse control. They tend to perform poorly in school, which reduces their earning potential as adults. They also face an increased risk of kidney disease, stroke, and high blood pressure as they age. Research has found strong links between lead poisoning and incarceration for violent crimes.

Today, researchers estimate that approximately 500,000 American children still have high levels of lead in their blood. Health experts largely agree that there is no known “safe” blood lead level.

Where are the lead pipes?

The Biden administration’s plan calls for 100% replacement of lead service lines across the country – a goal the EPA aims to have in regulations by 2024. Step 1 is to find the pipes .

Most American cities have countless miles of lead service lines buried under streets and sidewalks and supplying people’s homes. Utilities do not know where many of these aging lines are located and do not have enough data to map them. Their replacement will require significant analysis, modeling, data and guesswork.

Old service lines have caused epidemics of lead poisoning in places such as Washington, DC; Flint, Michigan; and Newark, New Jersey. The chemistry is a little different in each case.

Workers removed water lines in Trenton, New Jersey on January 9, 2020. The city is replacing 37,000 lead lines over five years.Photo AP / Mike

Lead branch pipes generally develop a protective mineral “plate” on their interior walls after a short period of time, effectively separating the toxic lead pipe from the water passing through it. This coating, called scale, remains stable if the chemistry of the water passing through it does not change. But if this chemistry is altered, disaster can ensue.

In 2002, Washington, DC, switched from chlorine to chloramine for the treatment of its water supply. Chloramine is a more modern disinfectant that does not form dangerous reactive chlorine by-products like chlorine can.

This quickly corroded the protective plate lining the city’s pipes, draining the highly absorbable lead into the homes. Tens of thousands of children were exposed for two years before the problem was properly identified and addressed.

In Flint, state-appointed managers decided to save money during a budget crisis in 2014 by switching from water in Detroit to water from the Flint River. But regulators did not demand enough chemical analyzes to determine which additives should be used to hold the plate in the pipe. And they skipped the typical step of adding phosphate, which chemically binds to lead and keeps it from leaking out of pipes, to save about $ 100 a day.

The chemistry of corrosion is well controlled in many American cities, but it is not a perfect science. And utilities don’t always have detection systems that adequately alert water providers to tap hazards. Therefore, removing lead pipes is the only sure way to avoid the threat of new water crises.

Households can use some basic tests to identify water pipes that may be lead.

Cities will have to innovate

While $ 15 billion is a big investment, experts agree that replacing all lead pipes nationwide is not enough. For example, the estimated cost to replace all of Flint’s lead service lines is around $ 50 million – and there are thousands of US cities to repair.

My own town, Indianapolis, has a population of about 850,000 – about 10 times the size of Flint – and officials have only a rough idea of ​​where to find major service lines. There are ways to statistically model the probability that a given part of the water supply system has lead service lines, using information such as the size, location and dates of construction of the water lines. water, but they are imperfect.

Cities will need to be creative to make the most of the funds they get. As an example, I’m working with colleagues to develop a citizen science project that will deliver thousands of tests for lead to taps around Indianapolis. This effort, a partnership with the University of Notre Dame funded by the United States Department of Housing and Urban Development, may increase modeling with real-world data on lead levels in homes and will increase public awareness of the issue. .

Despite these challenges, I believe that greater urgency on this issue is long overdue. Each lead pipe replaced will mean higher lifetime incomes and lower disease rates for families who will have access to safer tap water.

This article was originally published on The conversation through Gabriel Filippelli at Indiana University Institute for Environmental Resilience. Read the original article here.


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