High School Students Develop an Inexpensive Filter to Remove Lead from Tap Water

March 28, 2022
The next generation of scientists and inventors is already finding approaches to address society’s problems. A group of high school students and their instructor report a solution to the problem of lead contamination in drinking water — an inexpensive faucet attachment that removes this toxic metal. Unlike conventional filters currently on the market, theirs includes a cartridge made with biodegradable plastic and indicates when it’s “used up” by turning the tap water yellow.
The researchers will present their results today at the spring meeting of the American Chemical Society (ACS). ACS Spring 2022 is a hybrid meeting being held virtually and in-person March 20-24, with on-demand access available March 21-April 8. The meeting features more than 12,000 presentations on a wide range of science topics.
“A few years ago, I saw a video of a woman in Michigan turn on her tap water, and it came out brown,” says Rebecca Bushway, who is the project’s principal investigator. She’s also presenting the work at the meeting. “That made me think — because there’s really no safe level of lead in drinking water, wouldn’t it be nice to have a water filter that could tell you that your water is contaminated, well before it turns brown because of lead?”
Although some pipes have been remediated in the U.S., millions of homes, especially those in low-income communities, still receive drinking water through lead-containing pipes. If the water’s chemistry isn’t ideal, or it flows quickly because of high demand, then pipes can corrode. When the corroding material contains lead, the toxic metal dissolves or flakes off into the water, contaminating it with a dark discoloration and sometimes visible particles.
Until old pipes can be replaced with lead-free versions, filters can help remove or reduce this pollutant from tap water. Although various lead filtration systems exist, their high cost and large size can be barriers. In addition, few of them provide any indication that they should be changed, and none indicate that the water could pose an immediate health risk.
Bushway, a science teacher at Barrie Middle and Upper School, wondered aloud to her upper-level high school chemistry class if there was a little filter — similar to the ones that are made for camping to purify water — that they could make from inexpensive components to easily remove lead. The students were excited about the idea, and they started thinking about the project in 2020 when COVID-19 restrictions kept them out of the classroom. While at home, the team met virtually and discussed designs for an attachment to screw a filter onto a sink’s faucet. Then in the spring semester of 2021, when they returned to the classroom, they 3D printed the attachment and a 3-inch-tall filter housing, using a biodegradable plastic. Their final step was to fill the cartridges with a mixture of calcium phosphate and potassium iodide powder.
“Calcium phosphate first binds with dissolved lead in water to form lead phosphate and free calcium. The calcium, which is harmless, ends up in the water, and the lead phosphate stays in the filter,” explains Bushway. Lead phosphate, which is an inert solid, is trapped inside the filter by a nylon screen on the bottom of the unit. Once the reaction capacity of the calcium phosphate is reached, dissolved lead reacts with potassium iodide, which turns the water yellow, an indicator that lead is present.
And while the chemistry itself is pretty straightforward, crafting the water filtration system to do what the researchers intended has been more complicated. For instance, calcium phosphate tends to clump up, causing the reaction rate between it and lead to go down as the surface area decreases. So, the team’s lead student engineer incorporated hexagonal bevels inside the filter. “That’s an innovation, which came from one of the high school students, that will make the water spiral as it goes through and keep the powder from clumping,” says Bushway.
Next, the students will add a tiny spectrophotometer with a single-wavelength LED to the bottom of the filter cartridge, where the water gets dispensed. Their plan is to have an indicator light that turns on as soon as the detector identifies the yellow color of the lead iodide. Bushway says this will indicate that lead is in the water, even before the color is detectable by a human eye.
The team’s goal is to make and sell their filters for less than $1 each, which Bushway thinks they’re on their way to doing. Because the housings use biodegradable plastic, the cost could trend a little higher, but the material would help reduce the overall environmental impact of the filter.
The process of developing the filter has been very fulfilling, according to Bushway. “Ultimately, this experience has shown students that they can make a difference to somebody, and there are problems that they can fix with science,” she says.
The researchers acknowledge support from Barrie Middle and Upper School.
Proposed Standard for Hexavalent Chromium Prioritizes Public Health
TThe California State Water Resources Control Board recently announced a proposed maximum contaminant level (MCL) for hexavalent chromium that prioritizes protecting public health while considering the varying abilities of the state’s 7,000 public water systems, large and small, to invest in water treatment technologies to meet the new standard.
The proposal is an administrative draft only – the MCL will be considered for final adoption by the board after an extended public comment period and once recommended changes are considered. The proposal is a major milestone toward developing a new MCL for hexavalent chromium after the prior MCL was invalidated by a court that ruled the state did not adequately document if it was economically feasible for water systems to implement.
“We restarted the MCL analysis process from scratch, using updated data, and conducted a rigorous economic feasibility analysis, paying special attention to the range of possible impacts on water systems,” said Darrin Polhemus, deputy director of the State Water Board’s Division of Drinking Water. “Ultimately, a standard is a balancing of risks to public health and what is achievable for systems to implement successfully. The MCL for hexavalent chromium we are proposing – 10 parts per billion (ppb) – is a level that improves public health while providing water systems with a reasonable target and timeline to come into compliance.”
The State Water Board’s recent analysis shows that an MCL for hexavalent chromium of 10 ppb should be achievable for systems serving 95% of Californians. The analysis also shows that the remaining systems, which are mostly small and sometimes in low-income communities, may struggle with the financial and technical challenges of installing new treatment technology for hexavalent chromium. To aid these systems, board staff propose giving smaller systems a longer implementation period during which they can benefit from the research and development led by larger systems that must meet the standard first. Depending on the size of the system, the implementation period ranges from two to four years.
Hexavalent chromium, commonly called chromium-6, is an odorless and tasteless heavy metal that occurs throughout the environment and may occur in groundwater naturally or as a result of industrial sites that fail to follow proper disposal methods for contaminated waste. Studies have linked long-term exposure to a risk of cancer when ingested. At an MCL of 10 ppb, it is estimated that a person who ingests it daily for 70 years could have a one-in-2,000 chance of developing cancer.
The new MCL is expected to go into effect in early 2024, if adopted by the board.
New EPA Tool Provides the Public with Customized Updates on Local Enforcement and Compliance Activities
The EPA recently announced the release of a new web tool, called “ECHO Notify,” that empowers members of the public to stay informed about important environmental enforcement and compliance activities in their communities. Through ECHO Notify, users can sign up to receive weekly emails when new information is available within the selected geographic area, such as when a violation or enforcement action has taken place at a nearby facility. 
“EPA is committed to empowering communities with the information they need to understand and make informed decisions about their health and the environment,” said EPA Administrator Michael S. Regan.  “We’ve also seen that increased transparency leads to stronger deterrence of environmental violations. As more people play an active role in protecting their neighborhoods from pollution, EPA has developed ECHO Notify so that finding updates on environmental enforcement and compliance activities is as easy as checking your email.”
ECHO Notify provides information on all EPA enforcement and compliance activities as well as activities of state and local governments under the Clean Air Act, Clean Water Act, Resource Conservation and Recovery Act, and the Safe Drinking Water Act.  
You can find ECHO Notify on EPA’s website at ECHO Notify
Visitors to the ECHO Notify homepage who wish to receive email updates only need to take a few simple steps:
  • Create an account, if you don’t have one already
  • Select a geographic area and/or facility ID(s)
  • Choose the type of compliance and enforcement information of interest
  • Enter an email address
  • Click “subscribe”
Once subscribed, the user will receive an automated email (typically on Sunday) containing new information from the prior weeklong period. If no new information is available, no email will be sent. Email notifications include links for users to view additional information on ECHO, including a link to each facility’s Detailed Facility Report. Users can easily update their notification selections or unsubscribe at any time.
EPA has prepared a video that provides an overview of ECHO Notify and explains how to use it. The video can be seen here, ECHO Tutorial: Intro to ECHO Notify.
Minnesota Expands Search for PFAS to Nearly 400 Facilities
Citing the need to better understand where and how PFAS is being released into waters, air, and soil, the Minnesota Pollution Control Agency (MPCA) recently released its statewide PFAS monitoring plan that will initially focus on water testing and air emissions reporting at 379 facilities throughout Minnesota. Inclusion on the monitoring plan facility list does not necessarily mean a facility is releasing PFAS to the air, surface, or groundwater — it only means they have been identified as a potential emitter, and monitoring is a necessary initial step.
Twelve months ago, Minnesota laid out a comprehensive, long-term plan to protect families and communities from harmful PFAS contamination,” said MPCA Commissioner Katrina Kessler. “This monitoring plan is the next phase of our commitment to better understand where and how PFAS is entering Minnesota’s environment.”
The list of facilities includes eight regional airports in Greater Minnesota — Bemidji, Brainerd, Duluth, International Falls, Hibbing, Rochester, St. Cloud, and Thief River Falls — where having PFAS-containing firefighting foam on site is required. An additional 137 manufacturing and industrial facilities will be asked to conduct additional monitoring. Ninety-one (91) wastewater treatment plants, including six Metropolitan Council facilities in the Twin Cities metro, have been included due to manufacturing and other industries in their communities.
The MPCA also expanded its search for PFAS to 143 active and operating landfills, recycling facilities, and composting centers. In March 2021, the MPCA announced that nearly 60 closed landfills in 41 counties had PFAS contamination in groundwater. The agency continues to determine the extent of contamination at those sites.
Minnesota’s PFAS monitoring plan is one of the most comprehensive approaches in the nation to understanding PFAS in our environment. PFAS, or Per- and polyfluoroalkyl substances, are a group of more than 5,000 man-made chemicals also known as “forever chemicals” because they do not break down in the environment. Some are known to cause serious health conditions.
The PFAS monitoring plan requests that the facilities conduct sampling and information reporting to the MPCA by the end of 2023. The MPCA is expected to release a summary of its findings in 2024. While other states like Colorado, California, and Connecticut have taken a more regulatory approach to address PFAS in the environment, Minnesota is using new monitoring data to work with facilities to make better-informed decisions about PFAS releases.
In addition to the monitoring plan, the MPCA highlighted additional legislative efforts this year to address PFAS, including: 
  • PFAS prevention grants: Governor Walz has requested $2 million to establish a PFAS prevention grant program to identify PFAS sources design projects to prevent PFAS pollution.
  • PFAS baseline conditions study: Governor Walz has requested $500,000 to determine ‘normal’ levels of PFAS found in soil or water and levels associated with local sources of pollution.
  • Wastewater PFAS reduction grants: Governor Walz has requested $2.175 million to provide technical assistance and grants to Greater Minnesota communities in their efforts to meet wastewater treatment pollutant limits and reduction requirements, including for PFAS.
The need for statewide measurement was particularly apparent when the MPCA listed several Greater Minnesota water bodies as impaired for PFAS contamination where there have not previously been concerns about PFAS.
Contractor Penalized for Discharging Sediment into Creek, Wetlands
A Clark County contractor has been given a $131,000 penalty after inspectors from the Washington State Department of Ecology found sediment and stormwater running off a construction site into nearby wetlands and Packard Creek. Rotschy, Inc. is developing a 319-lot residential subdivision in Ridgefield, Clark County. Ecology inspectors cited Rotschy, Inc. for nine water quality and permit violations between October 2021 and January 2022.
Ecology inspectors first witnessed permit violations during inspections in October and November 2021. Sediment and turbid construction stormwater were released into wetlands and Packard Creek from adjacent construction areas. Rotschy, Inc. was also directing construction stormwater through a pipe into nearby wetlands, which entered Packard Creek. The company failed to adequately stabilize the construction site, leading to erosion that released muddy construction stormwater offsite.
In December 2021, inspectors found additional erosion impacts, as well as stormwater being pumped from a stormwater pond into Packard Creek. Ecology repeatedly offered technical assistance to Rotschy, Inc. over the course of three months, but the violations continued. The company also did not follow best management practices, including phasing their construction to prevent erosion and uncontrolled discharges to waters, among other violations.
Stormwater runoff from construction sites can carry muddy water, debris, and chemicals into local waterways, which is why contractors like Rotschy, Inc. are required to follow the terms of a statewide Construction Stormwater General Permit. Once released, these sediments, chemicals, and debris can harm aquatic life and reduce water quality.
Massachusetts Manufacturer Cited for Safety Violations After Hot Liquid Plastic Burns Worker
A U.S. Department of Labor investigation found that a plastic packaging manufacturer – with a history of workplace safety and health inspections – could have prevented a worker at its Sterling facility from suffering severe burns if they had complied with OSHA’s requirements for lockout/tagout and provided personal protective equipment.
Investigators from OSHA determined that a worker for Berry Global, Inc. was sprayed with hot liquid plastic as they changed a screen on a plastic bag extruder machine on Sept. 23, 2021.
In the last five years, OSHA has inspected Berry Global, Inc. in various U.S. locations more than 40 times. These inspections include two fatality inspections in New Jersey and Wisconsin related to lockout/tagout violations. The company has contested both inspections.
Following its inspection in Sterling, OSHA found that the company failed to establish and use lockout/tagout procedures or eliminate employee’s exposure to protect workers from the extruder machine while they serviced or maintained it, did not train workers in lockout/tagout procedures, and did not conduct periodic inspections to ensure procedures were followed. OSHA also found that the company did not provide appropriate personal protective equipment to ensure that employees were protected when servicing the extruder.
OSHA cited Berry Global, Inc. for two willful violations and one repeat violation and has proposed $369,815 in penalties. Read the citations issued to Berry Global Inc.
“Berry Global, Inc. could have prevented this worker’s injuries if the company had followed required safeguards,” said OSHA Area Director Mary Hoye in Springfield, Massachusetts. “OSHA will hold employers accountable when they knowingly disregard their legal responsibility to provide workers a safe and healthful workplace.”
Berry Global, Inc. meets the requirements for the Severe Violator Enforcement Program because one of the proposed willful, and the proposed repeat citation, are high emphasis standards of lockout/tagout.
OSHA Reopens Rulemaking Record, Schedules Public Hearing on Proposed Final Rule to Protect Healthcare Workers from COVID-19 Exposure
OSHA has reopened the rulemaking record partially and scheduled an informal public hearing to seek comments on specific topics that relate to the development of a final standard to protect healthcare and healthcare support service workers from workplace exposure to the COVID-19 virus.
Submit comments online, identified by Docket No. OSHA-2020-0004. Submit written comments by the deadline of April 22, 2022.
Individuals interested in testifying at the hearing must submit their notice of intention to appear no later than 14 days after the publication of the Federal Register Notice. The hearing will begin on April 27, 2022, and will take place online. If necessary, the hearing will continue on subsequent days. Learn more in the Federal Register notice.
On June 21, 2021, OSHA issued an emergency temporary standard to protect workers in healthcare settings from occupational exposure to COVID-19. The Emergency Temporary Standard – which also served as a proposed rule – focused on healthcare workers most likely to have contact with people infected with the virus.
The agency is reopening the rulemaking record to allow for new data and comments on topics, including the following:
  • Alignment with the Centers for Disease Control and Prevention's recommendations for healthcare infection control procedures
  • Additional flexibility for employers
  • Removal of scope exemptions
  • Tailoring controls to address interactions with people with suspected or confirmed COVID-19
  • Employer support for employees who wish to be vaccinated
  • Limited coverage of construction activities in healthcare settings
  • COVID-19 recordkeeping and reporting provisions
  • Triggering requirements based on community transmission levels
  • The potential evolution of SARS-CoV-2 into a second novel strain
  • The health effects and risk of COVID-19 since the ETS was issued
As OSHA works towards a permanent regulatory solution, employers must continue to comply with their obligations under the General Duty Clause, Personal Protective Equipment and Respiratory Protection Standards, as well as other applicable OSHA standards to protect their employees against the hazard of COVID-19 in the workplace. More information, including compliance assistance materials, are available.
Free Amazon HD 10 Tablet with RCRA and DOT Training
Annual training is required by 40 CFR 262.17(a)(7).  Learn how to complete EPA’s new electronic hazardous waste manifest, and the more than 60 changes in EPA’s Hazardous Waste Generator Improvements Rule.  Environmental Resource Center’s Hazardous Waste Training is available at nationwide locations, and via live webcasts.  If you plan to also attend DOT Hazardous Materials Training, call 800-537-2372 to find out how can get your course materials on an Amazon Fire HD 10 tablet at no extra charge.
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