Air pollution choked Bangkok this morning as locals were urged to work from home due to the harmful levels of PM 2.5 particles in the atmosphere.

Parts of the city reached 289 on the Air Quality Index (AQI), making the capital the worst place in the world for smog caused by a combination of vehicle emissions, agricultural burning and stagnant weather.

AQI readings of above 50 are considered unhealthy and levels above 200 are regarded as severely dangerous. Long-term exposure can lead to respiratory conditions, infections and even cancers.

Bungling officials in Thailand have been unable to tackle the issue, which plagues the country every year between October and April.

Bangkok governor Chadchart Sittipunt meekly told residents to 'reduce outdoor activities' if they are affected and encouraged people to work from home.

Scientists found that smog is at its worst in the country when farmers burn waste crops to cheaply clear their land. This is combined with high numbers of polluting cars on the road and large construction projects across the capital.

The seasonal lack of wind and rain, combined with a winter low-pressure system in which cold air is trapped closer to the ground by warm air above – prevent the pollution from being dispersed naturally.

The Thai government has been criticised for failing to tackle the country's air pollution crisis, with bizarre measures such as spraying water into the air and giant purifiers having no impact.

Data scientist engineer Worasom Kundhikanjana said: 'PM 2.5 pollution has a seasonal trend in Bangkok and the northern provinces, but has only recently received public attention. During this winter haze, the harmful particle pollution level is high throughout the day, including on weekends.

'Unfortunately, spraying water into the air does not appear to be effective, since the volume of water is minuscule compared to actual rain.

'With the start of the monsoon season, the weather in Bangkok will get better, and public attention on this issue will likely fade. However, without immediate policy measures, the problem will come back again next winter.'