LEGASPI – (UPDATE 2) As Mayon Volcano continues to spew ash, the risk of respiratory and skin diseases becomes higher for thousands of residents here, health officials warned.

The volcano continued to rumble as it emitted clouds of soot that left a layer of ash on villages near Mayon, about 330 kilometers (200 miles) southeast of Manila, officials and eyewitnesses said.

Health officials warned that the tiny particles could cause respiratory problems or skin diseases, and could even affect the thousands of people crammed into evacuation centers outside the eight-kilometer (five mile) evacuation zone as they await the eruption that scientists said could come any day.

Eyewitnesses reported ashfall as far as 10 kilometers from the restive volcano.

The government's chief epidemiologist, Dr. Eric Tayag, said residents should stay indoors to avoid being exposed to the ash.

He said anyone who had to venture outside should wear long-sleeved clothes and cover their nose and mouth with a damp cloth.

The government’s chief volcanologist, Renato Solidum, said that the recent ashfall was the “most dangerous.”

"The main problem of the eruption from a distance is the fine ash which is being generated by the collapse of rock fragments from the lava flow," said Solidum.

"It's not very thick, just a few millimeters of ash but that is the most dangerous part because it is very fine ash," he warned in a television interview.

Mayon, which has been oozing lava and spewing ash for a week, remains at alert level four, meaning it could erupt any day said Solidum.

The elevated risk has prompted authorities to evacuate more than 9,200 families – over 44,000 people – from the danger zone.

With the continuous “intense volcanic activity,” Phivolcs also warned residents around Mayon to stay away from river channels on the southern sector of the volcano on fears of lahar flow.

“Active river channels and those perennially identified as lahar-prone [areas] in the southern sector should also be avoided especially during bad weather conditions or when there is heavy and prolonged rainfall,” the agency said.

Lava was also observed continuously flowing down the Bonga-Buyuan, Miisi and Lidong gullies, according to Phivolcs.

“The lava front has reached about five kilometers down slope from the summit along the Bonga-Buyuan gully,” it said.

Phivolcs reiterated its establishment of an eight-kilometer Extended Danger Zone (EDZ) from the summit on the southern sector and a seven-kilometer on the northern sector. These areas, the agency said, should be free from human activity.

“Areas just outside of this EDZ should prepare for evacuation in the event hazardous explosive eruptions intensify,” the agency warned.

The 2,460-meter (8,070-foot) volcano, which is famous for its near-perfect cone, erupted 48 times in recorded history. In 1814, more than 1,200 people were killed as lava buried the town of Cagsawa.