Also, the World Health Organisation (WHO) and the CDC state that an amount of lead in the body may be harmful, no matter how small, and that lead exposure could and should be prevented. Mr Chan seems unaware of these facts.

In his letter, he says that since lead water pipes were the norm in the last century, there is no cause for concern.

However, he fails to realise that despite its widespread use in the last century, lead is nonetheless a toxic substance.

The recent switch to pipes, paint and, partially, fuel without lead, which Mr Chan mentions, came about only in the 1990s as a result of research published at that time on the effects of lead exposure.

As science continues to make discoveries about the world around us, we must adjust our perceptions of what is safe and what is not safe accordingly. He goes on to question whether anyone has ever died due to exposure to lead. Thankfully, while most cases do not culminate in deaths, there have been fatalities caused by high levels of lead.

An example would the epidemic of lead-related deaths in Zamfara state, Nigeria, in 2010. Over a period of three months, 163 people died after being exposed to lead in the rocks and earth they were digging up. Therefore, lead poisoning in such situations can be fatal.

Data from the WHO and CDC should persuade us that we cannot be indifferent about the potential risk posed by exposure to lead.

Protest was about politics not race

In his letter about Singapore's Amos Yee ("Sometimes courts must get involved", July 26), John Chan has perhaps misapprehended the point I was trying to make ("Race should not be unthinkingly trotted out to gag free speech", July 20).

I was not seeking to defend Yee's actions nor question the due process of the Singapore courts. Rather, I objected to this newspaper's suggestion that the incident must inevitably be viewed through a racial and religious prism.

First of all, the case has nothing to do with race. Allusions to Singapore's multicultural nuances are irrelevant.

Second, the religious aspect is largely a red herring when examining the wider societal implications of this incident. Perhaps Yee was in technical breach of Singapore's strict laws against causing religious offence, but I find it hard to believe he would have been publicly hauled over the coals if he had likened Jesus Christ in a negative way to some unknown person.

The whole kerfuffle arose because Yee made offensive comments about Lee Kuan Yew in the wake of Lee's death. They outraged many Singaporeans including, I suspect, Mr Chan. Hence, my submission that this situation should really be looked at through a political and societal lens. Amos Yee stepped into a political minefield in Singapore, and is now paying the price.

In Hong Kong we have people selling toilet paper with Chief Executive Leung Chun-ying's image on it, where the intention is clearly to denigrate. Although this will almost certainly offend people, society and Mr Leung tolerate it in the name of freedom of expression. There is no public witch-hunt to persecute the seller of such a product.

The point here is not to opine on which level of freedom is better. It is to make clear that a society's tolerance for this type of expression is a political matter, not one of race or religion.

This year the Asian Youth Orchestra celebrates its 25th anniversary.

Is it not about time for Richard Pontzious, the orchestra's founder, artistic director, conductor, and promoter extraordinaire of culture and education, to be awarded a higher level of the local Hong Kong decoration to mark the event than the Bronze Bauhinia Star he already has?

People appear to want to brainwash us about the importance of reducing the stress levels we experience at work by setting a better work-life balance.

The argument is that we cannot find fulfilment in our lives if we do not achieve that balance.

However, if because of the nature of our jobs we are unable to reduce the workload and levels of stress and therefore do not get the right balance, will this put us under even more pressure?

Some people get a great deal of satisfaction from the work they do.

They feel proud of what they are doing and what they have achieved in their chosen careers.

They have good relationships with their colleagues because of the mutual support that exists, and they enjoy working as much as they enjoy life outside the office. Is the work-life balance relevant to such individuals?

Traditionally people worked from 9am to 5pm, but things change, especially with advances in technology and the culture of social media.

People will check emails relating to their jobs while in bed. They will work on documents outside the office, for example, while they are travelling on the train.

They will review presentations with their late-night cup of tea.

These are habits that have become a part of our everyday lives.

Given that for so many people, work starts taking over a more important role, we should learn to live with it rather than getting stressed about whether we are achieving that perfect work-life balance.

For those of us who really enjoy what we are doing in our careers, I think it is OK to be a workaholic.

However, it is also important to relish those moments when can enjoy ourselves outside the office and spend quality time with our loved ones.

When you are relaxing, you need to be able not to think about the office and enjoy the company of good, lifelong friends.

However, if people do not think they are achieving the perfect work-life balance, they should try not to get stressed over that.

They should just try to enjoy what they are doing.

I agree with those who argue that the drawbacks of the multiple-visit permits outweighed the advantages and that the switch to once-weekly visas for Shenzhen residents had to be implemented.

The issue of cross-border visitors has certainly sparked a fierce debate.

Some stakeholders argue that tourist-related industries will struggle to survive with the number of mainland visitors being limited.

They say that the influx of mainland tourists was good for the economy and helped make Hong Kong more prosperous. Pharmacies, boutiques, theme parks and hotels benefited. Also, they say new visa rules were not necessary as numbers had dropped off with many mainlanders opting for other destinations like South Korea and Japan.

On the other side of the argument are those who say the soaring number of visitors led to the growth of parallel traders and a rush on necessities such as infant milk in areas close to the border such as Sheung Shui.

They also talk about a proliferation of pharmacies at the expense of traditional local shops which were forced to close. And there were the confrontations between locals and mainlanders, sometimes because of cultural differences that damaged harmony in our society.

There is no point in having a society that is only money-minded. We need a stable society that ensures the livelihood of local citizens. Limits had to be placed on the numbers of mainland visitors.

Cathay must be sensitive to local cultures

Last month I was on Cathay Pacific flight CX700 from Colombo, Sri Lanka, to Hong Kong.

It was quite pleasant and comfortable except for one issue, which the airline authorities may have either ignored or are unaware of.

Before and during the flight, cabin announcements were made in English, Chinese (Cantonese and Putonghua) and Tamil.

The normal practice by airlines in making cabin announcements when the origin of the flight is not its home base is to use the language understood and spoken by the majority of the people in that country.

However, by making announcements in Tamil, Cathay was using a language understood and spoken only by about 20 per cent of the population, while ignoring the Sinhala language, which is understood and spoken by over 80 per cent of the population of Sri Lanka.

I urge Cathay Pacific to be sensitive to local cultures and languages when making cabin announcements.