Connect with us

Features

Environmental toxicants contribute to the alarming increase in the  frequency of Parkinson’s Disease and dementia 

Published

on

Elderly man with Parkinsons disease holds spoon in both hands

Since my retirement after working as a neurologist in the USA for over five decades, I have been spending a significant portion of time in Sri Lanka over the past few years.

A casual observation, without detailed research, is that there seems to be a significant increase in Parkinson’s Disease (PD) and dementia among the urban population, where air pollution is the highest. Such increase serves to confirm recent international studies that have indicated that the incidence of the frequency of these diseases is increasing worldwide at an alarming rate.

In Asia, both China and India have the highest incidence of PD and it is estimated that by 2050, PD will become a public health issue. Many of these studies conclude that the primary factor responsible for this increase is the heightened exposure to toxicants in the environment.

PD is a neurodegenerative disease that is due to loss of dopaminergic neurons in an area of the brain called the substantia nigra, responsible for using dopamine as a neurotransmitter. Dopamine not only acts on the areas of the brain which produce feelings of pleasure, stimulation and satisfaction, it also plays a role in controlling memory mood, sleep, learning, movement and other bodily functions. The damage to this subset of dopaminergic neurons is due to accumulation of the protein alpha synuclein (Lewy bodies) that damages the neurons that stops the dopamine, contributing to the onset of PD.

Symptoms of PD related to motor functioning include a resting tremor, paucity of movement, limb stiffness and gait and balance problems. However, there are additional non-motor symptoms that include dementia, autonomic nervous system dysfunction such as blood pressure control. Although there are therapies to lessen the severity of motor symptoms, this disease runs a progressive course.

There are many factors that cause of PD and about two percent of all cases is due to specific genetic mutations. Some of the genetic abnormalities that have been identified are cases where they are inherited as autosomal dominant diseases (SCNA, LRKK2, VPS35 genes are implicated). Others are inherited as autosomal recessive conditions (Parkin, PINK1, Dj1, ATP13A2 genes are implicated). Interestingly, in about 20% of PD patients, mutations in one allele of the glucocerebrosidase gene (GBA gene) is a risk factor.

PD is currently is the fastest growing neurological disease, worldwide. However, this increase can neither be explained by our improved ability to diagnose PD nor can it be attributed to an increasing life span. Furthermore, the increase of PD is unlikely to be due to increased frequency of gene mutations in relevant genes.

A colleague at the Johns Hopkins School of Medicine, Dr Ray Dorsey, published several papers including a book implicating environmental factors as the primary cause for this increasing frequency of PD. Dr. Dorsey concluded that the interplay between genetics with environmental factors is the most likely cause for this increased incidence. The environmental factors he has mentioned include airborne pollution, herbicides and pesticides (paraquat, DDT, agent orange), solvents (trichloroethylene) and heavy metals (manganese).

Manganese, a transition metal, is essential for steel production, the raw material for which is mined in countries such as Australia and South Africa. It has been known for some time that these miners, as well as welders, who are also subject to manganese exposure, have greater potential of being afflicted with PD. Other sources of manganese exposure develop when ground water is contaminated, and when exhaust emissions from vehicles pollute the air (since manganese is used in some fuel additives). Manganese causes oxidative damages to dopaminergic neurons in the substantia nigra, contributing to the onset of PD.

There are several environmental and other factors besides manganese exposure which play a role in the worldwide increase of the incidence of PD. In 1983, a research paper was published that a powder containing MPTP (synthetic heroin) administered intravenously or inhaled, resulted in some users in Northern California being afflicted with early onset of PD. Intensive research over the past six years has proved that MPTP is structurally similar to the pesticide Paraquat, a risk factor in the development of PD.

Investigators have brought attention to other toxicants such as solvents, pesticides and air pollution being responsible for the increased incidence of PD. The pesticides implicated in PD are Paraquat (similar structure to MPTP+) and Rotenone. Although the pesticides Paraquat, Rotenone, DDT and Heptachlor have been banned in the USA, Paraquat is still being used in countries such as Australia, Japan, India and Argentina.

I have had no access to the details of the use of different pesticides in Sri Lanka. However, it would be advisable for local authorities to monitor the use of pesticides and determine the incidence of these neurogenerative diseases amongst urban versus rural populations. A caveat to such studies is a lag time between exposure and the development of PD can be between 10 to 40 years.

A solvent that has also been implicated is Trichloroethylene (TCE). This solvent is widely used in the dry-cleaning industry, but also used for degreasing, decaffeinating coffee, for carpet cleaning, and for removal of paint. In the USA, the Environmental Protection Authority (EPA) has identified several sites where ground water has been contaminated with TCE. Since TCE is commonly used as a dry-cleaning agent, I am not certain whether such sites exist in Sri Lanka. The fact that exposure to TCE causes PD is similar to the way that pesticides cause damage to the nigrostriatal dopaminergic neurons, necessitates immediate investigation into this matter.

Finally, air pollution, where solid and liquid particulate matter (PM2.5) from fires, coal burning and vehicular traffic enter the brain through our nasal passage. PM2.5 are particulate matters of 2.5 diameter micrometers or less (like an aerosol) is associated with the greatest proportion of adverse health effects. Interestingly, since these toxicants enter via the nasal passages, decrease in the sense of smell may antedate the onset of PD. In Sri Lanka, by and large, air quality is poor and is primarily due to vehicular traffic. This was evident during the COVID lockdown period, when there was a remarkable improvement in the air quality throughout the island.

All of these toxicants affect an intracellular organelle called mitochondria, responsible for oxygen utilization and energy production. The functioning of the brain is highly dependent on energy; and although the brain is only three percent of our total body mass, it is responsible for over 20% of the oxygen utilized. Within the brain, the dopaminergic neurons are most energy dependent, so it stands to reason that toxicants that cause mitochondrial dysfunction and energy disruption in the brain will cause damage to dopaminergic neurons.

Turning to dementia, there are many forms that include Alzheimer’s disease, vascular dementia, frontotemporal dementia (FTD) and Lewy body dementia (LBD). I do not know which form of dementia is most prevalent in Sri Lanka, though I have seen cases of FTD and LBD. Lewy body accumulation in neurons is due to misfolding and accumulation of the protein alpha-synuclein. In a recent published manuscript, investigators demonstrated that particulate matter (PM2.5) may be responsible for LBD. Their conclusions were based on worldwide epidemiological research and supported by experimental studies.

When mice were exposed to fine airborne particles, PM2.5 obtained from different regions such as the USA, Europe and China, these particles from the different regions, all produced alpha-synuclein accumulation in neurons. The investigators concluded that these airborne particles entered the brain and caused misfolding of alpha-synuclein protein resulting in damage to the neuron. Finally, there is a considerable amount of research being conducted aimed at understanding the role of air pollution in the pathogenesis of Alzheimer’s disease.

Given the overwhelming evidence, it behooves the Sri Lankan government to take immediate and drastic measures to tackle increasing air pollution, a national problem which impacts the quality of life, decreases the incidence of heart, lung and brain diseases. Moreover, measures taken to decrease such health-related problems would alleviate the exigencies of the nation’s already overburdened healthcare system and would, in the long term, be cost-effective.,

An old Thomian, Gihan Tennekoon obtained his medical degree from Guy’s Hospital, London. Post graduation, he transferred to the Johns Hopkins School of University School of Medicine, in Maryland, USA, for training and research in the field of neurology. He served as an Associate Professor at John Hopkins from 1969 to 1991, when he moved to the University of Pennsylvania as the Grace Loeb Professor, responsible for the direction of the Child Neurology Program.

Tennekoon is currently Professor Emeritus at the University of Pennsylvania.

by Gihan Tennekoon  ✍️



Continue Reading
Click to comment

Leave a Reply

Your email address will not be published. Required fields are marked *

Features

Rebuilding Sri Lanka Through Inclusive Governance

Published

on

Management Committee of the 'Rebuilding Sri Lanka' Fund Appointed with Representatives from the Public and Private Sectors - PMD

In the immediate aftermath of Cyclone Ditwah, the government has moved swiftly to establish a Presidential Task Force for Rebuilding Sri Lanka with a core committee to assess requirements, set priorities, allocate resources and raise and disburse funds. Public reaction, however, has focused on the committee’s problematic composition. All eleven committee members are men, and all non-government seats are held by business personalities with no known expertise in complex national development projects, disaster management and addressing the needs of vulnerable populations. They belong to the top echelon of Sri Lanka’s private sector which has been making extraordinary profits. The government has been urged by civil society groups to reconsider the role and purpose of this task force and reconstitute it to be more representative of the country and its multiple  needs.

 The group of high-powered businessmen initially appointed might greatly help mobilise funds from corporates and international donors, but this group may be ill equipped to determine priorities and oversee disbursement and spending. It would be necessary to separate fundraising, fund oversight and spending prioritisation, given the different capabilities and considerations required for each. International experience in post disaster recovery shows that inclusive and representative structures are more likely to produce outcomes that are equitable, efficient and publicly accepted. Civil society, for instance, brings knowledge rooted in communities, experience in working with vulnerable groups and a capacity to question assumptions that may otherwise go unchallenged.

 A positive and important development is that the government has been responsive to these criticisms and has invited at least one civil society representative to join the Rebuilding Sri Lanka committee. This decision deserves to be taken seriously and responded to positively by civil society which needs to call for more representation rather than a single representative.  Such a demand would reflect an understanding that rebuilding after a national disaster cannot be undertaken by the state and the business community alone. The inclusion of civil society will strengthen transparency and public confidence, particularly at a moment when trust in institutions remains fragile. While one appointment does not in itself ensure inclusive governance, it opens the door to a more participatory approach that needs to be expanded and institutionalised.

Costly Exclusions

 Going  down the road of history, the absence of inclusion in government policymaking has cost the country dearly. The exclusion of others, not of one’s own community or political party, started at the very dawn of Independence in 1948. The Father of the Nation, D S Senanayake, led his government to exclude the Malaiyaha Tamil community by depriving them of their citizenship rights. Eight years later, in 1956, the Oxford educated S W R D Bandaranaike effectively excluded the Tamil speaking people from the government by making Sinhala the sole official language. These early decisions normalised exclusion as a tool of governance rather than accommodation and paved the way for seven decades of political conflict and three decades of internal war.

Exclusion has also taken place virulently on a political party basis. Both of Sri Lanka’s post Independence constitutions were decided on by the government alone. The opposition political parties voted against the new constitutions of 1972 and 1977 because they had been excluded from participating in their design. The proposals they had made were not accepted. The basic law of the country was never forged by consensus. This legacy continues to shape adversarial politics and institutional fragility. The exclusion of other communities and political parties from decision making has led to frequent reversals of government policy. Whether in education or economic regulation or foreign policy, what one government has done the successor government has undone.

 Sri Lanka’s poor performance in securing the foreign investment necessary for rapid economic growth can be attributed to this factor in the main. Policy instability is not simply an economic problem but a political one rooted in narrow ownership of power. In 2022, when the people went on to the streets to protest against the government and caused it to fall, they demanded system change in which their primary focus was corruption, which had reached very high levels both literally and figuratively. The focus on corruption, as being done by the government at present, has two beneficial impacts for the government. The first is that it ensures that a minimum of resources will be wasted so that the maximum may be used for the people’s welfare.

Second Benefit

 The second benefit is that by focusing on the crime of corruption, the government can disable many leaders in the opposition. The more opposition leaders who are behind bars on charges of corruption, the less competition the government faces. Yet these gains do not substitute for the deeper requirement of inclusive governance. The present government seems to have identified corruption as the problem it will emphasise. However, reducing or eliminating corruption by itself is not going to lead to rapid economic development. Corruption is not the sole reason for the absence of economic growth. The most important factor in rapid economic growth is to have government policies that are not reversed every time a new government comes to power.

 For Sri Lanka to make the transition to self-sustaining and rapid economic development, it is necessary that the economic policies followed today are not reversed tomorrow. The best way to ensure continuity of policy is to be inclusive in governance. Instead of excluding those in the opposition, the mainstream opposition in particular needs to be included. In terms of system change, the government has scored high with regard to corruption. There is a general feeling that corruption in the country is much reduced compared to the past. However, with regard to inclusion the government needs to demonstrate more commitment. This was evident in the initial choice of cabinet ministers, who were nearly all men from the majority ethnic community. Important committees it formed, including the Presidential Task Force for a Clean Sri Lanka and the Rebuilding Sri Lanka Task Force, also failed at first to reflect the diversity of the country.

 In a multi ethnic and multi religious society like Sri Lanka, inclusivity is not merely symbolic. It is essential for addressing diverse perspectives and fostering mutual understanding. It is important to have members of the Tamil, Muslim and other minority communities, and women who are 52 percent of the population, appointed to important decision making bodies, especially those tasked with national recovery. Without such representation, the risk is that the very communities most affected by the crisis will remain unheard, and old grievances will be reproduced in new forms. The invitation extended to civil society to participate in the Rebuilding Sri Lanka Task Force is an important beginning. Whether it becomes a turning point will depend on whether the government chooses to make inclusion a principle of governance rather than treat it as a show of concession made under pressure.

by Jehan Perera

Continue Reading

Features

Reservoir operation and flooding

Published

on

Floods caused by Cyclone Ditwah

Former Director General of Irrigation, G.T. Dharmasena, in an article, titled “Revival of Innovative systems for reservoir operation and flood forecasting” in The Island of 17 December, 2025, starts out by stating:

“Most reservoirs in Sri Lanka are agriculture and hydropower dominated. Reservoir operators are often unwilling to acknowledge the flood detention capability of major reservoirs during the onset of monsoons. Deviating from the traditional priority for food production and hydropower development, it is time to reorient the operational approach of major reservoirs operators under extreme events, where flood control becomes a vital function. While admitting that total elimination of flood impacts is not technically feasible, the impacts can be reduced by efficient operation of reservoirs and effective early warning systems”.

Addressing the question often raised by the public as to “Why is flooding more prominent downstream of reservoirs compared to the period before they were built,” Mr. Dharmasena cites the following instances: “For instance, why do (sic) Magama in Tissamaharama face floods threats after the construction of the massive Kirindi Oya reservoir? Similarly, why does Ambalantota flood after the construction of Udawalawe Reservoir? Furthermore, why is Molkawa, in the Kalutara District area, getting flooded so often after the construction of Kukule reservoir”?

“These situations exist in several other river basins, too. Engineers must, therefore, be mindful of the need to strictly control the operation of the reservoir gates by their field staff. (Since) “The actual field situation can sometimes deviate significantly from the theoretical technology… it is necessary to examine whether gate operators are strictly adhering to the operational guidelines, as gate operation currently relies too much on the discretion of the operator at the site”.

COMMENT

For Mr. Dharmasena to bring to the attention of the public that “gate operation currently relies too much on the discretion of the operator at the site”, is being disingenuous, after accepting flooding as a way of life for ALL major reservoirs for decades and not doing much about it. As far as the public is concerned, their expectation is that the Institution responsible for Reservoir Management should, not only develop the necessary guidelines to address flooding but also ensure that they are strictly administered by those responsible, without leaving it to the arbitrary discretion of field staff. This exercise should be reviewed annually after each monsoon, if lives are to be saved and livelihoods are to be sustained.

IMPACT of GATE OPERATION on FLOODING

According to Mr. Dhamasena, “Major reservoir spillways are designed for very high return periods… If the spillway gates are opened fully when reservoir is at full capacity, this can produce an artificial flood of a very large magnitude… Therefore, reservoir operators must be mindful in this regard to avoid any artificial flood creation” (Ibid). Continuing, he states: “In reality reservoir spillways are often designed for the sole safety of the reservoir structure, often compromising the safety of the downstream population. This design concept was promoted by foreign agencies in recent times to safeguard their investment for dams. Consequently, the discharge capacities of these spill gates significantly exceed the natural carrying capacity of river(s) downstream” (Ibid).

COMMENT

The design concept where priority is given to the “sole safety of the structure” that causes the discharge capacity of spill gates to “significantly exceed” the carrying capacity of the river is not limited to foreign agencies. Such concepts are also adopted by local designers as well, judging from the fact that flooding is accepted as an inevitable feature of reservoirs. Since design concepts in their current form lack concern for serious destructive consequences downstream and, therefore, unacceptable, it is imperative that the Government mandates that current design criteria are revisited as a critical part of the restoration programme.

CONNECTIVITY BETWEEN GATE OPENINGS and SAFETY MEASURES

It is only after the devastation of historic proportions left behind by Cyclone Ditwah that the Public is aware that major reservoirs are designed with spill gate openings to protect the safety of the structure without factoring in the consequences downstream, such as the safety of the population is an unacceptable proposition. The Institution or Institutions associated with the design have a responsibility not only to inform but also work together with Institutions such as Disaster Management and any others responsible for the consequences downstream, so that they could prepare for what is to follow.

Without working in isolation and without limiting it only to, informing related Institutions, the need is for Institutions that design reservoirs to work as a team with Forecasting and Disaster Management and develop operational frameworks that should be institutionalised and approved by the Cabinet of Ministers. The need is to recognize that without connectivity between spill gate openings and safety measures downstream, catastrophes downstream are bound to recur.

Therefore, the mandate for dam designers and those responsible for disaster management and forecasting should be for them to jointly establish guidelines relating to what safety measures are to be adopted for varying degrees of spill gate openings. For instance, the carrying capacity of the river should relate with a specific openinig of the spill gate. Another specific opening is required when the population should be compelled to move to high ground. The process should continue until the spill gate opening is such that it warrants the population to be evacuated. This relationship could also be established by relating the spill gate openings to the width of the river downstream.

The measures recommended above should be backed up by the judicious use of the land within the flood plain of reservoirs for “DRY DAMS” with sufficient capacity to intercept part of the spill gate discharge from which excess water could be released within the carrying capacity of the river. By relating the capacity of the DRY DAM to the spill gate opening, a degree of safety could be established. However, since the practice of demarcating flood plains is not taken seriously by the Institution concerned, the Government should introduce a Bill that such demarcations are made mandatory as part of State Land in the design and operation of reservoirs. Adopting such a practice would not only contribute significantly to control flooding, but also save lives by not permitting settlement but permitting agricultural activities only within these zones. Furthermore, the creation of an intermediate zone to contain excess flood waters would not tax the safety measures to the extent it would in the absence of such a safety net.

CONCLUSION

Perhaps, the towns of Kotmale and Gampola suffered severe flooding and loss of life because the opening of spill gates to release the unprecedented volumes of water from Cyclone Ditwah, was warranted by the need to ensure the safety of Kotmale and Upper Kotmale Dams.

This and other similar disasters bring into focus the connectivity that exists between forecasting, operation of spill gates, flooding and disaster management. Therefore, it is imperative that the government introduce the much-needed legislative and executive measures to ensure that the agencies associated with these disciplines develop a common operational framework to mitigate flooding and its destructive consequences. A critical feature of such a framework should be the demarcation of the flood plain, and decree that land within the flood plain is a zone set aside for DRY DAMS, planted with trees and free of human settlements, other than for agricultural purposes. In addition, the mandate of such a framework should establish for each river basin the relationship between the degree to which spill gates are opened with levels of flooding and appropriate safety measures.

The government should insist that associated Agencies identify and conduct a pilot project to ascertain the efficacy of the recommendations cited above and if need be, modify it accordingly, so that downstream physical features that are unique to each river basin are taken into account and made an integral feature of reservoir design. Even if such restrictions downstream limit the capacities to store spill gate discharges, it has to be appreciated that providing such facilities within the flood plain to any degree would mitigate the destructive consequences of the flooding.

By Neville Ladduwahetty

Continue Reading

Features

Listening to the Language of Shells

Published

on

The ocean rarely raises its voice. Instead, it leaves behind signs — subtle, intricate and enduring — for those willing to observe closely. Along Sri Lanka’s shores, these signs often appear in the form of seashells: spiralled, ridged, polished by waves, carrying within them the quiet history of marine life. For Marine Naturalist Dr. Malik Fernando, these shells are not souvenirs of the sea but storytellers, bearing witness to ecological change, resilience and loss.

“Seashells are among the most eloquent narrators of the ocean’s condition,” Dr. Fernando told The Island. “They are biological archives. If you know how to read them, they reveal the story of our seas, past and present.”

A long-standing marine conservationist and a member of the Marine Subcommittee of the Wildlife & Nature Protection Society (WNPS), Dr. Fernando has dedicated much of his life to understanding and protecting Sri Lanka’s marine ecosystems. While charismatic megafauna often dominate conservation discourse, he has consistently drawn attention to less celebrated but equally vital marine organisms — particularly molluscs, whose shells are integral to coastal and reef ecosystems.

“Shells are often admired for their beauty, but rarely for their function,” he said. “They are homes, shields and structural components of marine habitats. When shell-bearing organisms decline, it destabilises entire food webs.”

Sri Lanka’s geographical identity as an island nation, Dr. Fernando says, is paradoxically underrepresented in national conservation priorities. “We speak passionately about forests and wildlife on land, but our relationship with the ocean remains largely extractive,” he noted. “We fish, mine sand, build along the coast and pollute, yet fail to pause and ask how much the sea can endure.”

Through his work with the WNPS Marine Subcommittee, Dr. Fernando has been at the forefront of advocating for science-led marine policy and integrated coastal management. He stressed that fragmented governance and weak enforcement continue to undermine marine protection efforts. “The ocean does not recognise administrative boundaries,” he said. “But unfortunately, our policies often do.”

He believes that one of the greatest challenges facing marine conservation in Sri Lanka is invisibility. “What happens underwater is out of sight, and therefore out of mind,” he said. “Coral bleaching, mollusc depletion, habitat destruction — these crises unfold silently. By the time the impacts reach the shore, it is often too late.”

Seashells, in this context, become messengers. Changes in shell thickness, size and abundance, Dr. Fernando explained, can signal shifts in ocean chemistry, rising temperatures and increasing acidity — all linked to climate change. “Ocean acidification weakens shells,” he said. “It is a chemical reality with biological consequences. When shells grow thinner, organisms become more vulnerable, and ecosystems less stable.”

Climate change, he warned, is no longer a distant threat but an active force reshaping Sri Lanka’s marine environment. “We are already witnessing altered breeding cycles, migration patterns and species distribution,” he said. “Marine life is responding rapidly. The question is whether humans will respond wisely.”

Despite the gravity of these challenges, Dr. Fernando remains an advocate of hope rooted in knowledge. He believes public awareness and education are essential to reversing marine degradation. “You cannot expect people to protect what they do not understand,” he said. “Marine literacy must begin early — in schools, communities and through public storytelling.”

It is this belief that has driven his involvement in initiatives that use visual narratives to communicate marine science to broader audiences. According to Dr. Fernando, imagery, art and heritage-based storytelling can evoke emotional connections that data alone cannot. “A well-composed image of a shell can inspire curiosity,” he said. “Curiosity leads to respect, and respect to protection.”

Shells, he added, also hold cultural and historical significance in Sri Lanka, having been used for ornamentation, ritual objects and trade for centuries. “They connect nature and culture,” he said. “By celebrating shells, we are also honouring coastal communities whose lives have long been intertwined with the sea.”

However, Dr. Fernando cautioned against romanticising the ocean without acknowledging responsibility. “Celebration must go hand in hand with conservation,” he said. “Otherwise, we risk turning heritage into exploitation.”

He was particularly critical of unregulated shell collection and commercialisation. “What seems harmless — picking up shells — can have cumulative impacts,” he said. “When multiplied across thousands of visitors, it becomes extraction.”

As Sri Lanka continues to promote coastal tourism, Dr. Fernando emphasised the need for sustainability frameworks that prioritise ecosystem health. “Tourism must not come at the cost of the very environments it depends on,” he said. “Marine conservation is not anti-development; it is pro-future.”

Dr. Malik Fernando

Reflecting on his decades-long engagement with the sea, Dr. Fernando described marine conservation as both a scientific pursuit and a moral obligation. “The ocean has given us food, livelihoods, climate regulation and beauty,” he said. “Protecting it is not an act of charity; it is an act of responsibility.”

He called for stronger collaboration between scientists, policymakers, civil society and the private sector. “No single entity can safeguard the ocean alone,” he said. “Conservation requires collective stewardship.”

Yet, amid concern, Dr. Fernando expressed cautious optimism. “Sri Lanka still has immense marine wealth,” he said. “Our reefs, seagrass beds and coastal waters are resilient, if given a chance.”

Standing at the edge of the sea, shells scattered along the sand, one is reminded that the ocean does not shout its warnings. It leaves behind clues — delicate, enduring, easily overlooked. For Dr. Malik Fernando, those clues demand attention.

“The sea is constantly communicating,” he said. “In shells, in currents, in changing patterns of life. The real question is whether we, as a society, are finally prepared to listen — and to act before silence replaces the story.”

 

By Ifham Nizam

Continue Reading

Trending