Ten years ago, I wrote a column that I entitled “No lead is good lead.” The column raised a number of eyebrows and is still quoted today. Actually, that column was written well after my first involvement with lead. I first got involved with lead in drinking water concerns in the early 1980s. I was interviewed for the Chicago local news in 1986 regarding lead in the Chicago drinking water.
When I was invited to participate in the development of a new standard involving plumbing products and water quality, I jumped at the opportunity. That committee eventually developed the first edition of NSF 61, Drinking Water System Components – Health Effects, which was published in June 1988. The standard celebrated its 30th year last June.
NSF 61 is adopted by every plumbing code. It is also adopted by just about every state in the nation. For the states that don’t directly adopt NSF 61, it is adopted in the state’s plumbing code. Hence, there is a mechanism for enforcing the standard.
NSF 61 is developed by The NSF Joint Committee on Drinking Water Additives. I have been a member of that committee since its inception. The committee meets once a year, the week after Thanksgiving. This year’s meeting had a full agenda.
One of the hot topics continues to be lead in drinking water. There were multiple issue papers presented on lead in drinking water. If you are wondering why there is a renewed interest in lead, a lot has to do with recent headlines in newspapers, news reports, and social media regarding lead in schools and lead in the water supply in Flint, Michigan.
While this may appear to be a renewed interest, realize that lead in drinking water is part of the discussion at every meeting of The NSF Joint Committee on Drinking Water Additives. Lead was, and still is, a major concern. No lead is good lead.
During this past year’s meeting of The NSF Joint Committee on Drinking Water Additives, one of the speakers basically stated that the plumbing industry isn’t doing enough. That may not be exactly what the speaker said, but that is what I heard.
As I was listening to the presentation, I became more and more infuriated. What I was hearing was that we, as a profession, have been ignoring the problem of lead in drinking water for all these years. Now we have to do something.
Before I could enter into the conversation, I had to calm down, realize that the speaker was new to the work of the Joint Committee and remember to be polite. All too often, I concluded, we become defensive rather than entering into rational conversations.
Has the plumbing industry done enough to reduce the lead in drinking water? Maybe. Could the plumbing industry do more to reduce lead in drinking water? Again, maybe. This is what started a long conversation.
The first thing every engineer should understand is that NSF 61 only permits lead to be used in copper alloy (brass and bronze) products. Lead is banned in all other plumbing products. Prior to the outright ban of lead, it was used as a stabilizer in certain plastic plumbing products. It was also used in the lubricating oils of many other plumbing products. The stabilizers and lubricants using lead are out, banned by NSF 61.
The amount of lead permitted by NSF 61 is the same as the federal requirements, -0.25% or less. However, the standard further requires testing for lead concentrations in drinking water. The maximum allowable lead concentration is 5 parts per billion (ppb). To put it mildly, that is a very small value. Test results have shown that many products are well below the 5 ppb, lower than 1 ppb.
The NSF Joint Committee on Drinking Water Additives voted to develop a new procedure that allows a copper alloy manufacturer to test its product to a lower lead level than the 5 ppb. If the product meets the lower level, it could then use a marking, as well as advertising, that the product meets a more stringent lead concentration level when tested to NSF 61. The new procedure will be voluntary, not mandated by the standard.
A task group is currently developing the new protocol and marking. It is anticipated that the work should be completed sometime this year. Of course, it then must be approved by the committee before being published. This will provide an opportunity for engineers to specify a lower lead copper alloy product, if they so choose.
Getting back to the speaker raising an issue as to whether the industry has done enough. The questions the speaker asked are the same questions we should be asking when presented with a concern over test results showing lead in the drinking water. Some of the questions were:
- Where did the lead come from?
- How much lead was in the source water?
- Did you analyze the water piping system?
- How old is the water piping system?
- What was the amount of the first draw that you tested for lead?
- How far back in the piping system does the first draw take you?
Basically, you must become a forensic engineer, analyzing the water piping system to try and determine the source of lead. Don’t immediately think it is the faucet that is turned on to draw the water, or the water cooler that is tested in a school.
If you encounter a building where you cannot find the source of lead, yet the drinking water measures high concentrations of lead (more than 15 ppb) don’t immediately jump to the conclusion that the entire water distribution system must be replaced. Sometimes a simple solution can solve a local problem.
There are filters available that remove the lead from drinking water. It is impressive as to how good many of these filters are. However, one of the other concerns is that filters may also remove the disinfectant in the drinking water. Hence, if you recommend such filters, these are best locally installed just ahead of the plumbing fixture used to acquire the drinking water.
The worst thing you can do as an engineer is say, “Don’t worry about it.” If you hear of lead in drinking water, worry about it. Lead has no place in any drinking water.