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Panel answers questions on health effects of Horsham water contamination By Dan Sokil,, @dansokil on Twitter … Daily Local News

Panel answers questions on health effects of Horsham water contamination

By Dan Sokil,, @dansokil on Twitter

Posted: 09/01/16, 7:18 PM EDT | Updated: 6 hrs ago

Daily Local News

HORSHAM >> Several hundred residents of Horsham and the surrounding area now know a little more about the long-term health effects of contaminated groundwater in that area — and how much the experts still don’t know.

Even a relatively simple question, like whether the local water is safe for pregnant women or infants, can have a complicated answer.

“If the water is at the lifetime health advisory level or less than, it’s safe. We feel that people can use it,” said Karl Markiewicz, a senior toxicologist with the Center for Disease Control’s Agency for Toxic Substances and Disease Registry’s Philadelphia office.

“That standard was developed to protect the most sensitive sector — in this case, it’s an infant breastfeeding — so the short answer is ‘yes,’” he said.

Markiewicz was among a panel of experts from state and federal agencies who answered questions during a public town hall, in one-on-one sessions with residents and in a public question-and-answer discussion Monday night at Hatboro-Horsham High School.

Karen Johnson, chief of groundwater enforcement for the federal Environmental Protection Agency’s Region 3, described a long list of household products that have been used since the 1950s and contain PFOA (perfluorooctanoic acid) and PFOS (perfluorooctanesulfonic acid), both linked to firefighting foams used at the former Willow Grove and Warminster bases and detected in groundwater now.

“PFOS and PFOA are both eight-carbon chains, and they’ve been used for many products that have saved time for us. They’re used to resist stains, grease, as water repellant,” Johnson said, showing a list of former and current uses.

PFOAs have long been used in cooking surfaces such as Teflon, toothpastes, shampoos, cosmetics, food containers, paints and cleaning products, while PFOS has been used in photo development, semiconductors, stain repellents — and both can be found in flame repellents, including the firefighting foams used at the bases until 2010. Every five years, EPA promulgates a new list of chemicals to regulate and at what level to do so, and that process led to a new health advisory level being issued by EPA earlier this year, from the previous 400 parts per trillion of combined PFOA and PFOS to a new standard of 70 parts per trillion.

“The health advisory is currently based at 20 percent of our consumption being from drinking water. The other 80 percent of these, PFOS and PFOA, is from some of the other ingestions: toothpaste, cosmetics, dust — that really can’t be addressed,” she said.

Studies have shown that PFOA and PFOS are only slowly absorbed through skin contact and more quickly by ingestion, according to Johnson and Markiewicz. A resident asked whether private wells over the 70 PPT advisory level are safe to use for gardening, watering the lawn or filling a swimming pool, and the answers vary.

“The short answer is ‘yes’ for the lawn — it doesn’t really stay in the surface soil; it wants to move down to the groundwater. For gardens, there is very, very little plant intake,” Markiewicz said.

Dermal absorption — through the skin — while swimming should be minimal, and swallowing a small amount while swimming may also not be harmful, even to children, he said.

“It’s not as if they’re drinking glasses full of it, but they may drink a mouthful or two, and that’s going to be a low amount. So what we’re telling folks is that you can use it for those purposes,” he said.

Sharon Watkins, director of the Pennsylvania Department of Health’s Bureau of Epidemiology, described the results found by analysing data on cancer cases from 1985 through 2013 (the last year data is available) in the Warminster, Warrington and Horsham ZIP codes.

“This cancer analysis provides, I would say, a mixed picture. We found both increases and we found decreases for the concerns of potential interest in this area, as opposed to statewide rates,” she said.

Kidney and liver cancer occurrences were within expected ranges for all age groups. Rates of bladder cancer were slightly higher in the Warminster ZIP code (18974) from 2005 to 2013, but were lower than the expected level for the Warrington ZIP code (18976) in the 1985-’94 period and at the expected levels from 1995 to 2004. Rates of non-Hodgkin’s lymphoma did show occasional increases, but at different times for different age groups, the data did not show any distinct trends, she said.

“We didn’t see, for both males and females, in all three periods, elevation for any of the cancers, so that makes it a little more difficult to say ‘Aha!’ in this kind of analysis,” said Watkins.

“But, we are very cognizant that we did identify a few statistically increased results for the cancers of potential interest,” she said, naming testicular cancer and non-Hodgkin’s lymphoma as cancers where rates increased enough to warrant further study.

What is the best way for residents to filter or purify their own water? Johnson said the EPA does not certify devices for their effectiveness in removing PFOA or PFOS, and any lab that would test that filtration must be clean and have no Teflon or other potential contamination sources.

“It’s on the horizon, but it’s not available at this time,” she said.

If soil is excavated from the Horsham base as part of a redevelopment project, could the PFOS and PFOA get into the air? Dawn Ioven, an EPA toxicologist with the Philadelphia regional office, said PFOA and PFOS typically move through soil into groundwater relatively quickly, and anyone doing the excavating would likely suppress that dust.

“If we do find PFCs in soil, and that soil has to be excavated. There would also be measures to ensure that any contamination in that soil would not become airborne, and that would eliminate the inhalation pathway,” she said.

Could pets be impacted by PFOA or PFOS? Few studies have been done on animals that typically are house pets, Markiewicz said, and the only study he’s seen on dogs looked at how the chemicals passed through their bodies, not the health effects. Studies on mice or rats may be comparable to pet guinea pigs or other animals of the same size, but little information is available for larger pets.

“That question comes up a lot, and we really don’t have an answer, and there aren’t any standards we use for comparisons for farm animals or pets,” he said.

Are the air bases the only sources of PFOA and PFOS contamination? No, Johnson said, because they’re used frequently in the household cleaning products and cosmetics, although some manufacturers are starting to phase them out.

“We have all used these products. We flush them down the drains, they go into our sewers, into our wastewater systems. We really don’t have the expectation that we will get to zero” levels of PFOA or PFOS, she said.

“What we have are those hot spots,” like the two bases, “and those areas are pretty well-defined, but given the values that we’re finding across the world, you basically have this in our soil and water worldwide.”

Horsham resident state Rep. Todd Stephens, R-151, of Montgomery County, asked why the EPA said in February and October 2015 that infants should not ingest water with any levels of PFCs before issuing the long-term health advisory level in May 2016 of 70 parts per trillion.

“Why did EPA allow water that it said was not allowed for infants to flow out of the faucets in our homes?” Stephens said.

Rick Rogers, associate director of the EPA’s State Programs Branch for the Mid-Atlantic region, said that warning was issued out of “an abundance of caution” because final studies were still underway at that time on the impact of PFOA and PFOS on infants.

“At the time, we couldn’t say for sure what the level should be for infants. Now we know, it’s 70 [parts per trillion], so we’re saying, ‘At 70 or below is OK for infants.’ At the time, our knowledge was a little bit not-settled in that department,” he said.

State Rep. Madeleine Dean, D-153, of Philadelphia, said she understood the “feeling of unease” her constituents have expressed because so much remains unknown about the long-term effects of exposure to PFOA and PFOS.

“I think that there’s a lot of information known, and there’s probably even more information that’s not known,” Dean said.

U.S. Rep. Brendan Boyle, D-13, of Montgomery County, said he was glad to work with fellow U.S Reps. Mike Fitzpatrick, R-8, of Bucks County, and Patrick Meehan, R-7, of Chadds Ford, to ensure federal attention to the local residents who live in all three of their districts.

“I wish we didn’t have this issue to deal with, but at no point has our different party affiliations come up since we’ve been working on this,” he said.

“We’ve had more conversations, the three of us, on the House floor about this issue than all the other issues combined, so it is a quite serious one and something we’ve been dealing with on a bipartisan basis, and we’ll continue to do so,” Boyle said.

All presentations from the panel will be posted on Horsham’s website,, according to township Manager Bill Walker, and a frequently asked question (and answer) list will be developed based on feedback from the experts. For more information, visit or email for updates.



Erik A. Ross


Milliron & Goodman Government Relations, LLC.

200 North 3rd Street

Suite 1500

Harrisburg, PA 17101

Phone:  717-232-5322

Cell:  717-574-3963

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