With Holloway and Pentonville prisons, there are two very large areas of land in public ownership, write Andrew Gardner and Zena Sullivan, Islington Archaeology and History Society and Rachel Krish, Margins Project, Union Chapel, Islington.

This is where purpose-built social housing should be the priority. The numbers on the council waiting list are known, and it is hard to estimate the numbers of “sofa surfers”. Considering the prisons were and are “home” to a number of our fellow citizens, it makes sense the land should site new homes for local people who, through taxes, funded these institutions. The land should not be sold off, but handed to Islington Council to build suitable, genuinely affordable accommodation for some of the many thousands on the local waiting list.

The Mount Pleasant site alone could have solved the entire housing needs of Clerkenwell. The Holloway and Pentonville sites present a once-only chance to address the immediate housing needs of Islington.

The Metropolitan Borough of Finsbury was the first to introduce its own council housing. There is an opportunity for Islington to build on its legacy. We have one chance to do this.

I have lived in a a street near Highbury Fields since 1982, writes Tim Sayer, Highbury, full address supplied.

Over the past few years, I have watched the increasing use of barbecues on the Fields with some concern. I have become involved in the campaign to ban or limit the BBQs, whose petition has been signed by more than 800 people so far. Clearly, they don’t all live in houses on the Fields. A lot of hot air has been expended on the issue and so I thought I should contribute a potted history of events leading to the start of the campaign, and how it has fared.

In May 2011, an Islington Council officer wrote a report recommending the ban on barbecues in green spaces in the borough be scrapped. Three weeks later, the lifting of the ban was announced. There was no public consultation or any proper health and risk assessment, including regarding fires.

Since then, with widespread continuing publicity, the use of BBQs has increased. Islington is the only London borough that allows unrestricted use of barbecues, which means a large proportion of users come from further afield. With this increased use, Highbury Fields is fast becoming a free party destination – as shown by the presence of huge barbecue units, professional chefs and caterers.

On a warm day, the so-called main “mother field” is overwhelmed with large crowds and barbecues, causing smoke pollution, rubbish, environmental degradation (carbon dispersion, burnt grass), more traffic, safety risks (fires, broken glass, abandoned hot charcoal). The Fire Brigade has spent some fifteen thousand pounds attending fires on the Fields since the BBQ ban was lifted. Local people who wish to enjoy the fresh air are deterred from doing so.

Two studies measuring pollution in the form of particulate matter, PM2.5, have been completed. Both indicate extremely high levels of PM2.5 in the mother field when barbecues take place; the level is two to three times worse than in the busy Marylebone Road.

The smoke, soot, fumes and particulate matter are breathed in by the users themselves, envelop the mother field and blow towards and into homes. Ash is deposited on window sills. The air quality deteriorates. On still days, the pollution lingers. It is not solely a weekend occurrence – large crowds, barbecues and smoke pollution happen during weekdays as well.

Many scientific studies have shown the deleterious effects of particulate matter – PM2.5 being especially dangerous. It is tiny and inhalable into the deepest recesses of the lungs. It can cause smarting eyes, coughs, sore throats, difficulty with breathing, strokes, heart attacks, lung cancer, heart disease and stunting of lung growth in children in the longer term. It can exacerbate asthma and increase hospital admissions, and it is implicated in diabetes and dementia. It is not just particulate matter and soot emitted from barbecues: fumes made up of volatile organic compounds are released from lighter fluid, binding material, kerosene, and accelerants added to charcoal to aid burning.

The council admits says there is only smoke pollution “on very few days of the year”. Last summer there were barbecues on 74 days, causing smoke nuisance on a significant number. I also disagree with the council’s assertion that “this is a worthwhile trade-off to ensure people are able to to use and enjoy their local park over the summer”. There is evidence residents’ health is seriously affected by the smoke, especially the elderly and those with lung diseases. These people can’t walk across the mother field to go shopping, see their doctor, or simply enjoy fresh air. They are forced to take taxis to get round the mother field and avoid the smoke, something many can ill afford.

The council’s claim there is no risk to public health is irresponsible and negligent (supported ostensibly by research from its own public health department). Islington is adamant residents without gardens should be able to enjoy barbecues on the fields – but those of us without gardens particularly need green spaces where we can breathe fresh air. And those with respiratory problems, those with young children, and those who want to walk dogs don’t want to miss out on Highbury Fields on warm days. Our message is simply this: why not encourage picnics and ban barbecues, so we can all enjoy fresh air? Please sign the petition at you.38degrees.org.uk/petitions/save-highbury-fields.