The kidney is a primary site of lead accumulation as it is excreted by the kidneys. Pb is the induction of mitochondrial oxidative stress and inflammation. (Image: Freepik)
New Delhi: Delhi continues to breathe poor air conditions. On Wednesday morning, the national capital witnessed a “very poor category” of air quality, while the air quality levels have degraded even more. Delhi has been noticing a steep rise in AQI levels after a marginal development on Sunday but on Monday, the city’s AQI stood at 348 at 4 pm from 301 recorded on Sunday. The depleting air quality conditions have caused various health issues ranging from respiratory illnesses to headaches and eyeburn but what are the worst impact of air pollution?
In conversation with News9, Dr Kshitij Raghuvanshi, Robotic and Laparoscopic Urologist, at Ruby Hall Clinic Pune said, “Environmental air pollution may be composed of different Particulate Matter (e.g. PM10 and PM2.5–10), gaseous pollutants [e.g. nitrogen dioxide (NO2), carbon monoxide (CO), sulphur dioxide (SO2) and ozone (O3)] and heavy metals [e.g. cadmium (Cd), lead (Pb) and mercury (Hg)]. Another global public health issue, chronic kidney disease (CKD) is associated with a number of unfavorable outcomes, including early mortality. It is thought to be an equal risk factor for cardiovascular disease (CVD).”
Hidden Link Between air quality and kidney health
Now there have been many studies around the world proving that air pollution is also responsible for the deterioration of renal health along with lung-related issues.
Arsenic – High levels of urinary Arsenic may increase the risk of developing CKD by 4-fold. Acute As-induced renal intoxication may lead to tubulointerstitial nephritis and acute tubular necrosis causing increased calcium and protein in urine, nephrocalcinosis and necrosis of the renal papillae.
Cadmium – Environmental tobacco smoke exposure was the most important determinant of Cd status in school-aged children. As a direct nephrotoxic, CD can cause gradual loss of glomerular filtration rate (GFR) and renal tubular damage, including polyuria and generalised tubular failure, or Fanconi syndrome. It is believed that prolonged exposure to Cd will accelerate the GFR reduction associated with CKD.
Lead – The kidney is a primary site of lead accumulation as it is excreted by the kidneys. Pb is the induction of mitochondrial oxidative stress and inflammation. This results in lipid oxidation and DNA damage. Early-life exposure to low levels of lead (Pb) results in glomerular hypertrophy, which can interfere with glomerular growth. Acute Pb intoxication causes proximal tubular dysfunction (Fanconi syndrome), and chronic intoxication leads to progressive tubulointerstitial nephritis.
Mercury – All forms of Hg are nephrotoxic through various mechanisms. Hg has been linked to the development of CKD.
Uranium – Uranium toxicity, although relatively rare,(in the vicinity of nuclear reactors) may also cause renal damage and indeed, the kidney is the primary target for uranium toxicity following inhalation or ingestion. The complexed uranium in proximal tubules dissociates as the pH drops, releasing the reactive uranyl ion that can interact with the membrane of the proximal tubule.
Smoking – Direct or passive smoking harms the kidneys. Cigarette smoke has been associated with idiopathic nodular glomerulosclerosis and microalbuminuria or overt proteinuria in healthy individuals. Smoking promotes the progression of hypertensive and diabetic nephropathies. Renal fibrosis has also been linked to passive smoking.
Traffic-related air pollution – In one of the studies it was found that 1-year exposures to traffic-related air pollution were associated with lower eGFR, higher CKD prevalence and increased risk of CKD progression among the elderly. Higher PM levels are associated with higher BP levels, which is a risk factor for CKD.
Both NO2 and PM2.5 were associated with higher fasting glycaemia and insulin, lower insulin sensitivity and higher insulin secretion and have been associated with Diabetes Mellitus, which can lead to CKD in the long run.