KUALA LUMPUR, June 20 – Haze from neighbouring Indonesia sent air pollution readings in Johor off the chart today and engulfed the southern part of the state in noxious smog that has caused a surge in patients complaining of respiratory issues.

According to the Meteorological Department, the air pollutant index (API) topped 380 by afternoon in Muar – the worst on record – after starting the day at 337, The Star reported on its website today.

By official measures, API readings between 51 and 100 are considered “moderate”, while the 101 to 200 range is considered “unhealthy”. Air quality between 201 and 300 is “very unhealthy” while “hazardous” is applied to API scores topping 300.

API readings at Pasir Gudang and Kota Tinggi both also drifted into the second-worst rung.

This morning, some kindergartens in Muar had sent their wards home owing to the choking haze, with schools in the area following suit shortly after.

Health practitioners in nearby Batu Pahat reported a blanket increase in patients seeking treatment for breathing problems, with some citing as much as a 30 per cent rise in such cases.

“Some complained that the haze this time is worst as the air is not only cloudy, but also carries ashes and fine particles,” clinician Dr King Ban Siang was reported as saying in The Star’s report.

One pharmacist also said supplies of face masks and filters were already exhausted.

“We are out of stock at the moment. Sales of Vitamin C and fever reduction (medication) will also go up every time the haze comes,” according to the unnamed pharmacist.

The haze is expected to persist throughout today because of the wind direction.

Satellite imaging also showed a surge in the number of hotspots in Sumatra, with 376 detected today, up from 187 on Tuesday; on Monday, it had been 113.

Southeast Asia’s worst haze crisis took place in 1997-1998, causing widespread health problems and costing the regional economy billions of dollars as a result of business and air transport disruptions.

The now-annual affair triggered allegedly due to land-clearing activities by plantation firms in Indonesia has also caused friction among the ASEAN neighbours, with regular bouts of finger-pointing over which was ultimately to blame for plunging the region into smog.