He has walked non-stop for six days, covering 387km in temperatures as low as minus 40 deg C.
Conditions at the 6633 Arctic Ultra race have been extreme, but Mr Toh Poh Joo is not about to give up - not when he has covered about 70 per cent of the race and is also ahead of the pack.
Mr Toh, 41, is now second in the ongoing event, which started on March 11. He hopes to raise $50,000 for The Straits Times School Pocket Money Fund through public donations.
He needs to walk 566km over eight days across Canada, from the Yukon to Tuktoyaktuk, while carrying his own provisions in a cart. He is allowed two supply drops of gear and food, and can get hot meals and accommodation only at specific checkpoints.
Mr Toh, a Changi Airport Group vice-president of ground operations and customer service, took on the race as a personal challenge, both physically and emotionally.
Making a personal appeal on his Facebook page, he said: "Hope you can donate generously to The Straits Times School Pocket Money Fund, a charity that I personally believe in."
As a child, he sometimes went to school without any pocket money to buy food with during recess. He drank tap water to fill his stomach.
By raising money for the fund, he hopes to prevent children from low-income families going hungry at school. The fundsupports about 14,000 children and youth a year.
He raised $53,000 for the fund in 2008 by organising his own mall marathon. Of the total amount raised, $25,000 came from the CapitaLand Hope Foundation, the charity arm of real estate company CapitaLand.
The only Singaporean and the only Asian in the race, Mr Toh is just behind Romanian Tiberiu Useriu. About two-thirds into the event, four out of 12 racers have already dropped out because of various injuries, but Mr Toh is still going strong.
Said race director Martin Like: "You would struggle to find a man anywhere in the world who smiles as much as PJ (Poh Joo)."
- To make a donation and find out more about Mr Toh Poh Joo's Arctic expedition, visit the Giving.sg portal at https://www.giving.sg/the-straits-times-school-pocket-money-fund/arcticchallenge