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[Stayin' Alive]: Pollution 101

Talking with the doctor about water pollution vs. air pollution, why you shouldn't live in the basment, masks, and how your lungs will probably regenerate.
Last updated: 2015-11-09

Staying Alive is a regular column where we talk to doctors about common health problems in China. This is not a substitute for medical care – if you’re really ill, go see the doctor.

For this second round of Stayin' Alive, we talked pollution with Dr. Jorge Chedrauy, the Director of Family Medicine at the American Medical Center.

SmSh: Let's begin with the question on everyone's mind – are we literally taking years off our lives from living here and breathing the air?

Dr. Chedrauy: That's a tricky question. The fact of the matter is, every major city is polluted. Smoking will take years off your life, but if you're a long-term smoker (10-20 years) and you stop smoking, your risk of developing cancer would return to the same as the general population ten years after you stop smoking. So I guess in that sense, pollution would probably be the same.

Every major city is polluted, maybe some more than others. Shanghai is not as polluted as people think; there's other cities in China that are way worse. But you go to LA/Mexico city, same thing. And people live there, they live long lives…maybe they're affected by pulmonary diseases a little more than the rest of the world…It's a tricky question to answer. If you have comorbidities, if you have other diseases, it may affect you. But if you're a healthy person, you come here, you leave, you're probably gonna go back to baseline at some point.

SmSh: Everyone talks about air pollution. Do you think that's the most dangerous kind of pollution in Shanghai? Maybe water pollution or other pollution is worse?

Dr. Chedrauy: I think water pollution is probably worse than air pollution. Most of the time you're inside, you have your air purifier…but water, what are you gonna do with water? You buy vegetables, you wash them with water. You brush your teeth with that same water. You shower with the same water. I think air pollution is a little more under control. In that sense, I think water pollution is a little worse.

The thing with the water here is that it's full of chlorine, and what can you do with chlorine? You can have a filter that takes out the heavy metals, but chlorine…what are you gonna do with it, you know. And you're exposed to it on a daily basis.

SmSh: Is chlorine really bad for you?

Dr. Chedrauy: Chlorine is really bad for you…Even if you shower with it, you're gonna notice that your hair/skin dries up. Chroline is used to disinfect the water. Anything foreign in your body that causes side-effects such as dryness of your skin/mucosa, if you ingest that water you can have certain toxic levels of it in your blood. It's not good.

I've noticed that a lot of my patients come here and their eczema goes AWOL. The reason is that they shower every day with this nasty water and that's what happens.

SmSh: I lost my hair here…I don't know if that's because of chlorine or what…

Dr. Chedrauy: Maybe the process got accelerated [laughs]. The filters, the good ones [are] extremely expensive. If you wanna put a regular filter that just filters the heavy metals, yeah you're doing something but I don't think it's enough, to be honest. I think in that sense water pollution is worse than air pollution.

SmSh: So you were saying you can control air pollution with air purifiers – do you use one at home?

Dr. Chedrauy: I do, I have a Phillips. I don't remember the model, but it has several settings. If the space it's supposed to purify is too big, it shuts off or a light goes on. If the filter is too old, it shuts off until you change it. It's smart and it works very well.

SmSh: Do you notice a difference?

Dr. Chedrauy: That's the thing – you don't notice the difference. A lot of people think that just because you have an air filter at home, you're breathing fresh air. That's not the case. When you buy an air filter, there's several characteristics that you have to look into. If you have a 30sqm apartment and the air filter is for 20sqm, you're not doing much. So my advice is to always overshoot. The other one is how good the filters are. If you have to change the filters every month, it's probably not a good idea to buy something like that. But if the characteristics of the purifier fit the space, and it's a good brand, you should be good.

SmSh: We have this really nice air purifier in our office, but someone likes to keep the window open all the time – does that cancel all the good caused by the air purifier?

Dr. Chedrauy: There's actually some truth in not keeping the windows shut all the time. I normally sleep with the windows closed and I turn the air purifier on. But in the morning, I open the windows so the air flushes. I do that at night as well. When I leave the house I turn the purifier off but I close my windows. Letting the air flush in and out, that's always a good thing to do. A lot of people think that the pollution is only outside; they don't understand that there's pollution inside of your house. The paint on the walls/hardwood floor, the cosmetics, the sofa…that's all pollution. Rugs are terrible. So what they're doing is good, but not to leave the windows open the whole time – that defeats the whole purpose.

SmSh: A lot of homes in Shanghai have mold. How big of an issue is that?

Dr. Chedrauy: Pretty big. A lot of people think "I'm gonna buy a humidifier", but the humidity of a house should be between 35-55%. And if you turn the humidifier on all the time, you're gonna get mold everywhere. Fall season is mold season, right now. And mold causes allergies, mold causes asthma. Mold is a big issue in China.

SmSh: Is that worse than air pollution?

Dr. Chedrauy: If you are predisposed to allergies from mold, that's gonna affect you in more ways than one. And if you're asthmatic, that's gonna affect you. For sure. So a lot of people that are allergic, they turn the humidifier on because they cough at night, because the air is too dry…

SmSh: It's a vicious cycle. How about AC, do you use AC at home?

Dr. Chedrauy: You know, I haven't turned the AC on for a while [but] I do have central AC. I had the owners change it…it's more energy efficient and I wanted something new because I didn't know what was behind that. I normally change the filters every four-six months.

SmSh: Are there any days when you wear a mask?

Dr. Chedrauy: No, I never wear masks.

SmSh: Why not?

Dr. Chedrauy: You know, I consider myself healthy. And if you're just commuting to and from work, I really don't feel it's necessary. You gotta understand that there's differences in masks. There's the face masks that you see a lot of people wear that are made out of paper/cotton. It doesn't really fit your face properly, and you're not doing much with that. And there's the other type that are called respirators. They're serious and they really hug your face. Some of them have valves, and they're good.

I don't know if you've heard of the term N95…that means that they filter out 95% of particles that are 3 microns or bigger. And 3 microns is pretty small. There's [also] N98 and N100. They're pretty hardcore masks out there…Those are the ones that actually work. They're very tight to your face and they filter out everything.

SmSh: When you're wearing a mask, you're breathing in harder and deeper into your lungs, so does that counteract the positive effects of the mask?

Dr. Chedrauy: It depends on which mask you're using. If you're breathing harder when you're wearing a paper mask, yeah. But if you're wearing one of these hardcore masks, they actually do their job pretty nicely. But you gotta wear them on a daily basis. I never do. Once again I don't have allergies/comorbidities, so I don't do it. But I do encourage people that are asthmatic or suffer other pulmonary diseases to do that, especially here in Shanghai. The N95s, or if you can get your hands on something better, fine. They're approved by the FDA, so absolutely.

SmSh: Let's say someone is an asthmatic cigarette smoker, should they even bother wearing a mask when they go outside, or are they kind of fucked?

Dr. Chedrauy: [laughs] Well you know, one injury is better than two, so yeah. I would recommend it, especially on days when the AQI is high. You know, a lot of people are slaves to the AQI app. That I don't recommend. Check it out every once in a while, but to wake up every morning and in the afternoon and night and check it…You can't be a slave to that – you'll never be happy. It tells you an approximate number, and once again, most of the time you're inside.

SmSh: Can we actually see pollution? Sometimes the AQI is high but the sky is blue.

Dr. Chedrauy: That depends on what you call pollution. Smog you can see most of the time. The sunsets in California are red because of the smog. The term was coined back in the early 1900s in London when they were burning coal all the time. It's a portmanteau of smoke and fog.

SmSh: So is heavy smog what's driving up the AQI, or is it other stuff too?

Dr. Chedrauy: So PM2.5 means particles smaller than 2.5 microns. The EPA determined that any particle 2.5 microns and under is very hazardous for health, because normally the lungs can expel the crap, but when it comes to smaller particles it's very very tough. So the EPA came up with a formula to turn those particle matters less than 2.5 microns into an equation, and that's what the AQI is.

So smog is just particles suspended in the air combined with ozone and kickstarted with sunlight. [There's two layers of ozone]: one is the troposphere, which is from where we are up to maybe 20km up, and then the one in the stratosphere. That one is good. That's the one that filters the UV light, etc. But the one that's around here is the one that's really hazardous for us. That's where the smog is, that's what we breathe.

SmSh: So if you lived in the troposphere…oh wait that's 20km, that's higher than any building.

Dr. Chedrauy: Well actually, now that you mention that, living in a basement is way worse than living on the 30th floor. That's something you should keep in consideration. New floors, new furniture, all that stuff – the inside air pollution.

SmSh: Why is the basement bad?

Dr. Chedrauy: The basement is sometimes full of mold. Once again that causes asthma, allergic reactions, etc. And the air is not as pure as the air up there. You don't have to go up 20km, but if you're on the 30th floor you're way better than in the basement.

SmSh: So talking about lung regeneration. If you're a smoker for ten years and you quit, ten years later your lungs will really go back to baseline?

Dr. Chedrauy: Well, your risk of cancer would be back to baseline. Lungs actually have a pretty awesome way to heal themselves. So if you're out of that polluted environment, maybe you won't return to baseline health-wise, but your chances of living a regular, normal life after that are pretty good.

SmSh: Last question – are there really strong cancer risks from the pollution in Shanghai?

Dr. Chedrauy: I'm not sure…the chemicals in the air are pretty harsh, but once again you need to be predisposed to it to develop cancer. Most cancers do not happen de novo. Most cancers [happen] because you have a family history, or there's another theory called the knockout gene theory, where you have one gene that's cancerous and then you have another one that if you're exposed to something in the environment, both genes will cause cancer. That's in very layman's terms what happens, and that's one of the biggest theories of cancer. But to tell you that pollution is gonna cause cancer, it's too much of a generalization and I don't wanna say that. But it could be a contributor.


Dr. Jorge Chedrauy is the Director of Family Medicine at the American Medical Center and is also part of the American Board of Family Physicians.