The point is that people who contract cancer or heart disease, (which are largely diseases of old age), suffer less than people who suffer the effects of malnutrition and poverty.
From the perspective of our prosperous and comfortable lives in the developed world, pollution-induced diseases seems like a terrible affliction. And they are, relatively speaking.
But from the perspective of somebody living in the developing world, the diseases associated with poverty are even worse, and that is the thing that environmentalists living their comfortable lives in the developed world never seem to get.
However bad you think industry is, the alternative is worse. Despite all those pollutants, when a country industrialises it's life expectancy and general healthiness climbs. That's why the global population increased. And when people without it get the chance to industrialise, they grasp it enthusiastically. We in the developed world have forgotten what pre-industrial poverty was like – thank heavens! – and have a tendency to romanticise it.
As it happens, the biggest health risks from pollution are in the form of water-borne disease – cured by the industrial production and distribution of clean water – and indoor smoke from wood/dung cooking fires – cured by the industrial production and distribution of cheap energy as electricity or gas. Are all the people who contract lung diseases from indoor smoke supposed to just shut up and suffer for the good of the environment?
We need to prioritise our resources on tackling the most pressing problems first, with the best benefit/cost ratio, and then move down the list once those are solved. I agree that we need to do something about the dimwitted claim that we "put profits before people". Trade and markets are about people – they are the way we collectively work together to solve other people's problems, they are about efficiently allocating our limited time and talents to addressing the problems people find most important, and "profit" is simply a statement that the benefit achieved doing something should be worth more than the effort put in. "Profit" is actually a "people" concept – it's opposite is "waste" and is anti-people. 'Waste' is about expending the resources that could have quietly helped a hundred on a (usually more obvious or media-friendly) handful. It is about what is seen and what is not seen. But it is a difficult point to get across.