Saharan dust has returned with a vengeance across T&T over the past 48 hours, with air quality reaching levels that are unhealthy for the general population.
The Environmental Management Agency, which has a network of ambient air quality monitoring stations across both islands, said it has been recording air quality levels that are unhealthy for sensitive groups since Saturday evening.
Visibility at the Piarco International Airport in Trinidad and the ANR Robinson International Airport at Crown Point, Tobago, has been reduced to as low as four and eight kilometres, respectively.
The EMA added at this level, everyone may begin to experience health effects. Members of sensitive groups, such as children, the elderly, and those with cardiopulmonary ailments, may experience more severe health effects.
The authority explained these health effects included the increased aggravation of heart or lung disease premature mortality in people with cardiopulmonary disease and the elderly, and increased respiratory effects in the general population.
With air quality reaching unhealthy levels, sensitive groups were advised to avoid prolonged or heavy exertion and to move activities indoors. Everyone else was advised to reduce prolonged or heavy exertion and take more breaks during outdoor activities.
The EMA explained that high dust concentrations with a diameter of fewer than 2.5 micrometres (PM2.5) have been correlated with increased emergency room admissions for respiratory and cardiovascular disease in North America, Asia, and Europe. It added that the primary health concern associated with Saharan dust is particulate matter, microscopic dust (PM2.5 & PM10), which can sidestep the lungs’ natural defences. These tiny particles can contribute to cardiovascular problems and respiratory diseases such as asthma, especially in children and the elderly.
Although temperatures remain hot across Trinidad and Tobago, the EMA said keeping windows and doors closed to prevent Saharan dust from moving through homes was also advised, as well as using an air purifier and wearing a mask to conduct outdoor activities.
Initial peak dust levels occurred yesterday morning, but forecast models indicate that Saharan dust concentrations are forecast to fluctuate between moderate to high through the end of the week, according to the authority.
Recent data from the Trinidad and Tobago Meteorological Service (TTMS) suggested that the dust events have noticeably become more frequent. In the 1980s, Saharan dust was present between 25 to 35 days during the five to six-month span of the Dry Season. By 2020, this average increased to over 60 days during the same five to six-month Dry Season span. The TTMS also said the “monthly average [of] Saharan dust haze days and frequency varies significantly, but the proportion of dust haze days is highest in June followed by May and July. This period is the peak of the local Saharan Dust Haze Season.”