Case Studies

Case Study 1 – Family Expecting Baby in Jing’an Area Apartment


Ken C, Partner at a consulting firm, and a long-time Shanghai resident who moved from the US in 2003, and his wife Jamie, were expecting a baby and recently moved into an 7thfloor apartment in Jing’an district.  Like many new move-ins, they renovated, including repainting and adding new furniture.

Ken had heard about PureLiving through word of mouth and contacted us wondering how they could check out the safety of their new home.  He said, “We never thought much about the air or water before, but with a baby on the way, we wanted to make sure we did everything to prepare a safe environment.”

The first thing Louie Cheng, PureLiving founder and the couple’s advisor, did was to interview the couple to understand their building environment, activities, health situation, and capture any specific concerns.  This information helped identify potential pollutants to test for and create a customized testing strategy that avoided unnecessary costs.

  • Building environment: 167 m2 apartment, 5 year old building, wood floors, individual wall-mounted air conditioners, no existing air or water filtration
  • Occupant activities:  Husband occasionally smoked in the bathroom.  Wife cooked frequently.  No pets
  • Health sensitivities: None, but occasional headaches
  • Other complaints:  Foul odor in the bathroom and a chemical smell in the bedroom


We recommended a test strategy that focused on pollutants posing risk to the baby:

  • Particulate matter (PM2.5) – tiny airborne particles have been tied to decreased birth size and birth weight, particularly in male infants
  • Lead – exposure to lead in any amount retards physical and mental development and has been correlated to low IQ.
  • Nitrate (in water) – interferes with the bloods ability to carry oxygen to the brain, potentially resulting in “blue baby” syndrome where infants suffer brain damage
  • Carbon monoxide – colorless and odorless, carbon monoxide is released by incomplete combustion and is the second leading cause of accidental poisonings in the US

In addition, we tested for volatile organic compounds (VOCs), which are emitted by new furniture, paint, and other renovation materials.  Finally, we checked the water for dangerous levels of the most common pollutants in Shanghai: bacteria, chlorine, and heavy metals.

Test Results

Four problem areas were identified:

  1. Particulate matter – levels were recorded at 4-7x the US EPA allowable level for a 24-hour period
  2. Lead - Airborne lead at all points tested at about 6x the US EPA allowable standard.  The lead levels found in the soil in the building complex, including inside the children’s playground, was nearly double the EPA standards.
  3. Formaldehyde – the bedroom tested slightly above the Chinese national standard for formaldehyde, a pungent VOC and known carcinogen.
  4. Turbidity – the water tested 3x higher than the EPA standard for turbidity, a measure of the cloudiness of water.

Analysis and Remediation

Louie called the couple to walk through the results and discuss possible solutions.


-         Health Impact: Can lead to respiratory disease and infection, including asthma, shortness of breath, bronchitis, pneumonia, and also taxes the immune system.  Particulates increase blood pressure, the driver of stroke and heart attack.  Can also cause low birthweight and size

-         Sources: Outdoor air was the primary cause, based on high levels of particulates in Shanghai outdoor air and occupants’ habit of opening windows.

-         Solutions: Use a HEPA vacuum, purchase of a HEPA air purifier, and reducing external ventilation during peak traffic hours.


-         Health Impact: Extremely dangerous for fetus or young children as it can stunt growth and lead to hyperactivity, impaired hearing, and low IQ.

-         Sources: Given the elevated levels of lead in the soil outside and the occupants’ habits of wearing shoes in the house, external contamination was the primary source.  Cigarette smoke also contains lead, and could have been produced through indoor smoking

-         Recommendations: Use a doormat and remove shoes before entering the house.  We also recommended against any smoking in the house.  Finally, a HEPA air filter would help filter out airborne lead.


-         Health impact: Formaldehyde, a pungent VOC, frequently causes neurological reactions, including eye and throat irritation, headaches, and dizziness.  Long term exposure is linked to cancer, and the EPA named it a “known carcinogen” in 2010.

-         Sources: The elevated level was likely related to the glues or chemicals used in a new synthetic mattress mat

-         Recommendations: Air out the mattress pad and if smell didn’t reduce, discard.  Also, introduce specific indoor plants to reduce formaldehyde and produce oxygen


-         Health impact: Turbidity is a measure of the cloudiness of water caused by foreign or organic material.  Organic material can combine with chlorine to produce carcinogenic byproducts

-         Sources: Usually indicates secondary pollution or bacterial film from water piping

-         Recommendations: Install a sediment, activated carbon, or other physical water filter

In addition to the test result deficiencies, Louie was able to identify the bathroom odor as “sewer stink” resulting from a dry u-bend in the piping.  Filling this pipe eliminated the odor immediately.


Ken and Jamie followed most of the recommendations to modify their behavior and habits.  They also bought an air purifier to remove lead and particulates from the air.  “We didn’t realize that small changes like taking our shoes off or opening the windows during the day would have such a big impact,” says Ken.  “Making these changes cost us nothing but we wouldn’t have known to do it.”

The client, Ken had this to say about his experience with PureLiving China:

“What impressed me the most was that after we received the reports and the transaction supposedly ended, our consultant, Louie, conducted independent research to try to identify sources of the sewage smell in our bathrooms.  His research and suggestion was right on, and we were able to solve a problem that’s been plaguing us for a long time.  I certainly didn’t expect this level of service – PureLiving went above and beyond to delight a customer.”

Case Study 2 – Clean “Bill of Health” after Home Renovation in Pudong Area Villa

M moved to Shanghai from Switzerland with her husband and three children in January of 2011. And as we sat together to talk I could feel her long for the clean and unpolluted air of the Alps…

Shortly after moving into their house, a spacious villa in Pudong, her son called her to look at some worms that were coming out of small holes in the wood panels – termites were invading her new home! M recalls being very happy her furniture shipment had not arrived to Shanghai… She called management to have a look and they told her that they would need to spray. M wasn’t sure what it was they wanted to spray and was very concerned of the safety of the chemicals they would use. She didn’t agree to this and asked them to find another solution. The management glued the holes but just a few days later M and her family started discovering termites all around the house. Although termites don’t pose  a health hazard to human health the use of toxic pesticides to eradicate them can be detrimental to health.

At this point the only solution was to rip out all the wooding and renovate while M moved temporarily into another house. M insisted that she didn’t want the workers to spray insecticides in her home at any point during the renovations, and the management assured her that they wouldn’t.  So, she was shocked to discover during an unannounced  visit to the renovation site in her home that workers were in fact spraying. M told management she wouldn’t move back in before she was sure her indoor air quality was safe.

M contacted PureLiving to investigate.  Louie Cheng, founder of the Shanghai-based indoor environmental testing and consulting firm, researched Termidor, the pesticide used by the workers and discovered that whereas it was fairly ‘safe’ and inert it was still important to test the air and water to see if it was impacted by spraying.

The findings showed that the volatile organic compounds (VOCs) exceeded  the Chinese national health standard by nearly 400% and the US EPA’s standard by over 1000%.   Toluene, a chemical emission that is linked to kidney and liver damage, was also 250% higher.  Cheng attributed this to the paint used during renovations – “In China, the frequency of renovations means that low-emissions or “green” building materials are not widely used.” Since this is a very common occurrence post-renovation, especially if materials are not carefully chosen, living in a building with these levels of chemicals can lead to a range of health damage.. VOC’s can cause a range of neurological symptoms (headaches, fatigue, and nausea), eye and respiratory tract irritation. Long-term exposure to some VOCs is linked with liver and kidney dysfunctions as well as damage to the central nervous system.  Fortunately, there are solutions such as ventilating with industrial fans,  as well as treating rooms with Titanium Dioxide, which chemically reduces VOCs to harmless carbon dioxide.

PureLiving’s tests also  revealed that airborne lead was about 2.5 times that of the EPA safety standards (reflecting the low level of awareness of lead hazards, China does not have residential airborne lead standards and virtually no Chinese test companies know how to test for this). Lead exposure is linked with delays in growth, hyperactivity, impaired hearing, sterility and brain retardation. Children below the age of 6 are most at risk and the effects are irreversible but preventable.  “Lead can be generated through a number of sources within the home – smoking, burning certain candles, and tracking contaminated dirt into the home,” Louie explains.  “Shanghai air is already high in lead due to continued use of some leaded fuels, industrial processes, and the large amounts of coal burning.”  To treat the problem at home, Louie recommended using HEPA air filters to capture airborne lead, reducing external ventilation and HEPA vacuuming to capture settled lead dust.  In addition, he recommended that M test the blood lead level of her young children at the hospital to monitor exposure.

The assessment conducted by PL also determined that levels of particulate matter (PM) were nearly five times the EPA standards! PM can cause respiratory disease and infection and is correlated with diabetes and obesity in animals. Chronic exposure is linked to lung cancer and is a contributor to heart attacks and strokes by increasing blood pressure.  “Most particulates come from the outdoor air when we open doors and windows,” explained Louie, “ and since levels peak during the morning and late at night, it is better to avoid ventilating or doing strenuous outdoor activity during those times.” HEPA air filters  are also good options to reduce the presence of indoor PM.  PL recommends setting the filters on high for 30 minutes after ventilation.

Last but not least, the relative humidity exceeded guidelines for a healthy home.  . High levels of humidity can encourage the growth of mold, bacteria and mites,  all of which are allergens that can trigger asthma attacks or lead to the development of other allergies. Levels of humidity can be reduced by the use of air-conditioning and by running the exhaust fan when showering or cooking.  If you have floor heating, consider buying a dehumidifier that can remove 15-20L per day per large 30m2 room. The levels of humidity can be monitored by the use of a hygrometer, a device that PureLiving provided to M after testing.

Although the test results were alarming, M recalls that the PureLiving team was careful to reassure her that there were solutions and put the levels into context.  “Louie sent us a fair amount of scientific research to help us understand that toluene was not as dangerous as some of the other pollutants like formaldehyde or benzene.”  Also, during the face-to-face debrief, he prioritized the issues and laid out options to resolve each of them.  Some of the options cost nothing, while other ones, like treating the home with oxidizing reagents, would work quickly but cost money.  Eventually, the building management and M agreed to a PureLiving-recommended method of ventilation that used industrial fans, chemical-reducing indoor plants, air conditioning, and air purifiers.

After a one-week period, the PureLiving team returned to conduct a retest.  The results were dramatic:  the concentration of VOCs fell by an average of over 70% and toluene dropped over 95%.  “The retesting gave us the confidence to move back in with peace of mind that the problems had been resolved,” said M.

M feels happier and more at home here in Shanghai now that she’s taken actions  to make her house safer for her family. “I knew that living here meant that I would have to tolerate a certain level of uncertainty about health and safety,” she says “but both my husband and I had terminal cancer in our families and we intend to do everything in our power to protect our family.”

Case Study 3 –Health Check for Family in Pudong Area Villa

“My husband and I have been living in Shanghai for 8 years.  We love it here! Except for the pollution… But we didn’t decide to do anything about it until the moment we held our baby girl in our arms.”

S+X had no reason to suspect high levels of pollutants around them, nor did they have any health complaints to indicate harmful levels. X exercised in the garage and the only thing that really worried them was that the gas heater might be leaking carbon monoxide or other hazardous fumes. But like many expats who’ve grown accustomed to life in Shanghai and have little control over what happens outside, S+ X decided to make their nest the safest possible for their daughter.

S had already read an interview with Louie Cheng, the owner of PureLiving, an indoor environmental testing firm, on one of the expat forums and felt that it was a good service.  S quickly contacted PureLiving to describe their concerns and set up a meeting. “Talking to Louie gave us a level of confidence that we could improve things at home… he sounded calm and effectual.” On the date of their scheduled assessment of the indoor air and water quality of their house, “Louie personally showed up with an expert team, and after listening to our concerns carefully they went thoroughly thorough the house and did a full panel of tests. The assessment was informative and professional to a degree that exceeded my expectation and I was happy to find out that I was already doing some things right.”

Tests of air and  water quality  focused on elements that could be most harmful for an infant: lead, airborne particulates, nitrate and heavy metals. The results revealed some surprising health risks. Levels of airborne lead were 3-4 times higher than the US EPA’s standards for healthy air. Increased levels of airborne lead have been linked with decreased growth, hyperactivity and impaired hearing, sterility and negative impact on brain development. Children under six are most at risk. It is almost impossible to reverse the effects of lead poisoning but definitely preventable, so finding the problem early is key. Given the high levels of airborne lead PureLiving recommended a blood level baseline test to be done for S’s baby. Also to prevent further exposure PureLiving recommended the use of high efficiency particulate arrestance (HEPA) filters, reduced ventilation with outside air, and increased vacuuming to capture lead dust.

PureLiving also found lead in the varnish of the outside deck. The deck was built in 2011 while S+X lived in the house, S says she regrets not having been more involved in selecting the materials used to ensure nothing contained lead.

Among their findings, PureLiving detected an above normal range of particulates in several rooms. Particulate matter was 20% over the standards in the kitchen alone! Particulate matter can cause respiratory disease and infection such as asthma, shortness of breath, and bronchitis.  Even for healthy adults, Louie explained, high levels of particulates from coal soot, vehicle emissions, and fine dust from neighboring areas weigh heavily on our immune systems and increase the frequency of general illness.

Another important area of concern was the high relative humidity – which is the primary factor in leading to the growth of mold, bacteria, dust mites and cockroaches.   Some rooms in S&X’s home exceeded the  recommended level for a healthy home of 35-55% relative humidity. This could lead to the proliferation of dust mites, a particularly nasty problem that are the number- one indoor source of allergies. It was found that this was mostly due to the unnecessary use of humidifiers, a blocked dryer exhaust vent that the PureLiving team discovered, and not using exhaust fans in the kitchen and bathrooms.  Louie was also able to provide S with some inexpensive humidity meters to monitor the humidity levels easily.

During this process the PureLiving team also discovered another safety issue: dozens of rusty nail-studded boards left under her deck – which could have been potentially dangerous to her baby.  “This was something I assumed the building management would  have been careful to remove,” said S, and that she would not have found had it not been for Louie’s meticulous attention to the general safety of her home.

One benefit of getting their indoor air tested was that the results revealed that while levels of particulates were high, levels of chemical emissions or volatile organic compounds (VOCs) were within the safe range.  This meant that S&X did not have to purchase more expensive gas air filters, but could add the right type of filter for their specific problems.  “It’s important to first identify what’s wrong with a home’s indoor air quality before investing in air filters,” says Louie. “In many cases, there’s no need to spend thousands of RMB on filters and maintenance when other options are available.” Louie recommended several models of particulate filters that were cost-effective and offers negotiated discounts with most top brand filter dealers as a benefit for PureLiving clients.

One bright revelation was learning that both their tap water and bottled drinking water were well within safe limits for common pollutants.  This had been one of S&X’s largest concerns and now they had the assurance that they could safely use the filtered tap water for washing and cooking.  Louie also advised that they did not need to install shower filters, often needed in Shanghai to reduce dangerous levels of caustic chlorine.

S remembers calling her husband a little distressed after receiving the results. They agreed that while the assessment revealed problems, they were now fully aware of the “report card” status of the health and safety of their home environment and could implement PureLiving’s recommendations to improve the situation tremendously. After all said and done, S says, “We feel very empowered and we’ve done so much to make this house safer that it feels a little bit more like home to all of us.” Needless to say that S +X don’t plan on moving anytime soon!