研究表明，污染与儿童首次哮喘有关

The more children are exposed to pollution, the greater the risk they will develop their first case of asthma, a large study has found.

一项大型研究发现，暴露在污染环境中的儿童越多，他们患上第一次哮喘的风险就越大。

The study, published in the BMJ on Wednesday, adds to the growing evidence that exposure to air pollution influences the development of chronic breathing problems.

这项周三发表在《英国医学杂志》(BMJ)上的研究，进一步证明暴露于空气污染会影响慢性呼吸问题的发展。

Pollution linked to first time asthma
污染与首次哮喘有关

Doctors have long known that even brief exposure to air pollution can make asthma worse, but less is known about whether pollution raises the risk that children will develop asthma in the first place.

医生们早就知道，即使是短暂的暴露在空气污染中，也会使哮喘加重，但对于污染是否会增加儿童首次患哮喘的风险，人们知之甚少。

Researchers looked at data from nearly 780,000 Danish children born from 1997 to 2014. They followed up with the records to see if any of the children develop persistent wheezing and asthma between the ages of 1 and 15.

研究人员查看了1997年至2014年出生的近78万丹麦儿童的数据。他们对这些记录进行了跟踪，看看这些孩子在1岁到15岁之间是否会出现持续性的喘息和哮喘。

They found that children whose parents had asthma were also more likely to have asthma, as were children whose mothers smoked when they were pregnant.

他们发现，父母患有哮喘的孩子也更有可能患哮喘，母亲在怀孕期间吸烟的孩子也是如此。

But even when adjusting for these factors, it was when the children were exposed to higher levels of small particle pollution and nitrate pollution that they were more likely to develop asthma and persistent wheezing compared to children who were not exposed.

但是，即使对这些因素进行调整，与未暴露在高浓度小颗粒污染和硝酸盐污染中的儿童相比，暴露在高浓度小颗粒污染和硝酸盐污染中的儿童更容易患哮喘和持续性喘息。

For every additional 5µg-per-cubic-meter increase in concentrations of those pollutants, there was about a 4 or 5% increase in asthma or persistent wheezing.

每立方米这些污染物的浓度每增加5千克，哮喘或持续性喘息的发病率就会增加4%或5%。

Particle pollution
颗粒污染

Particle pollution comes from power plants, cars, construction, farming and fires. Particle pollution, instead of being breathed out, can get stuck in the lungs or go into the bloodstream. The particles can cause irritation and inflammation.

颗粒污染来自发电厂、汽车、建筑、农业和火灾。颗粒污染不会被呼出，而是会卡在肺部或进入血液。这些颗粒会引起刺激和炎症。

There are limitations to the study, since it is observational and relies on a model, and didn't look at children's specific personal exposure to pollution. There's an underlying assumption that children spent the majority of the time in the area of their residential address.

这项研究存在局限性，因为它是观察性的，依赖于一个模型，而且没有考察儿童个人具体接触污染的情况。有一种潜在的假设是，孩子们大部分时间都呆在他们居住的地方。

Personal air monitoring may add more detail to an assessment like this. There may also be other risk factors that couldn't be captured by the data since it lacked individual level information.

个人空气监测可以为这样的评估增加更多的细节。由于缺乏个人层面的信息，数据可能无法捕捉到其他风险因素。

Huge health impact

巨大的健康影响

Earlier studies have shown that even at low levels of small particulate matter pollution, children may be more likely to develop asthma than if they lived in an area with cleaner air.

早期的研究表明，即使小颗粒物污染水平较低，儿童也可能比生活在空气更清洁的地区更容易患哮喘。

Air pollution is believed to shorten the life expectancy of children by 20 months on average, according to a 2019 study.

根据2019年的一项研究，空气污染被认为会使儿童的预期寿命平均缩短20个月。

Exposure to pollution is also linked to heart problems, cancer, and premature death. And it's not just physical problems.

暴露在污染中也与心脏病、癌症和过早死亡有关。这不仅仅是身体上的问题。

A 2019 study found that even short-term exposure to high ambient air pollution corresponded with a rise in visits to the children's psychiatric emergency department for adjustment disorder, suicidal thoughts, and schizophrenia.

2019年的一项研究发现，即使短期暴露于高环境空气污染中，儿童精神病院急诊科因适应障碍、自杀想法和精神分裂症而就诊的人数也会相应增加。

This isn't a problem isolated to Denmark. According to the World Health Organization, around 93% of the world's children breathe air that is so polluted it puts their health and development at serious risk.

这不是丹麦独有的问题。根据世界卫生组织的数据，全球约93%的儿童呼吸的空气污染严重，严重威胁到他们的健康和发育。

The 2020 State of the Air report from the American Lung Association found that more Americans, more than 46% of the US, lived in communities impacted by unhealthy levels of pollution.

美国肺脏协会发布的《2020年空气状况报告》发现，更多的美国人(超过46%的美国人)生活在受不健康污染水平影响的社区。

That's higher than was found in past reports. Scientists think the climate crisis is making it even harder to protect human health, since warmer temperatures make air pollution a much bigger problem.

这比过去的报告发现的要高。科学家认为，气候危机使保护人类健康变得更加困难，因为气温升高使空气污染成为一个更大的问题。