The irresponsible behaviour of local food manufacturer Whye Kee Foodstuff is deeply troubling (Firm fined for illegally discharging liquid waste into sewers, Oct 9). The company was fined $14,400 for similar offences in May last year.

Another repeat offender is Tat Seng Packaging Group. In September 2016, it was caught illegally discharging copper-tainted water (Recalcitrant printing firm fined for pollution; March 20, 2018). It was fined a mere $12,000. Prior to that, it had been caught four times for polluting Singapore's sewers with toxic industrial used water.

National water agency PUB has mentioned that excessive levels of such liquid waste in the sewage can upset treatment processes at water reclamation plants and disrupt Newater production.

Newater is an important pillar for Singapore's water sustainability. Billions of dollars have been poured into its research and development.

Being a small country with few natural sources of water, Newater plays a pivotal role in Singapore's survival. To contaminate one of our main sources of water with toxic substances is a crime that is worse than a mere illegal discharge offence.

We should neither condone such irresponsible actions nor let these offenders off lightly.

The fine is clearly too low to deter such irresponsible acts. I believe our laws provide for holding an officer of a corporation responsible for an offence that has been proven to be committed by that corporation.

The full punishment includes a fine and/or imprisonment. I truly believe that recalcitrant offenders should face the full brunt of the law to deter such irresponsible actions that may bring catastrophic consequences to Singapore.

Foo Sing Kheng