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Pollution, Arsenic and possible solutions ...

Pollution, Arsenic and possible solutions ...

By Cristian Frers

Water is the most urgent need for human beings, despite this, very few populations have this element in sufficient quantity, since its distribution in the world is uneven. Help vegetation to thrive in some countries and let only deserts thrive in others.


Water is the most urgent need for human beings, despite this, very few populations have this element in sufficient quantity, since its distribution in the world is uneven. Help vegetation to thrive in some countries and let only deserts thrive in others. While there are regions where up to five meters of water fall annually, others receive 1,000 less.

Much of the fresh water is in the form of ice or is underground and difficult to access. Only 0.008% are found in lakes or rivers and circulate through easily accessible waters.

Water problems center on both quality and quantity. The community must know the importance of the “quality” of the same and that same community to take charge of its care and preservation.

The first to pollute the waters are pesticides and fungicides such as arsenic, carried to rivers by rain and soil erosion, whose dust flies into rivers or the sea and pollutes them. In addition, the fields lose fertility due to abuse of agricultural techniques. The salt carried in the winter from the roads to the rivers is another poisoning factor. The same as dikes and dams, which "sweep" wide swaths of crops. Agriculture accounts for around 70% of global water use.

If we take the example of Argentina, we will observe that almost all the water they consume comes from the same bodies of water in which sewage and industrial waste are evacuated. The concentration of various elements of pollution - heavy materials, bacteria, nitrates and hydrocarbons - that occur in different lakes, lagoons and rivers in Argentina, far exceed the figures considered dangerous.

It is no coincidence that the Paraná, Salado del Norte, Salado del Sur, Carcarañá, de la Plata and Colorado rivers are among the most polluted on the planet.

Argentina does not have adequate control measures for the treatment and disposal of sewage, solid hazardous waste, and household industrial waste, which ultimately end up contaminating surface and underground water bodies. There is information that determines that important and numerous bodies of water are affected by sewage, with intense eutrophication processes due to the lack of purification. The biggest problem is urban areas that receive wholesale pollutants from everywhere. One in four hospital beds is occupied by patients with water-borne diseases. Water pollution works slowly and causes diseases of all kinds, not just infectious disorders. Water carries metals and toxic substances that accumulate in organisms until they affect the various body tissues in different ways.

Surface water contamination from industrial wastewater and raw sewage is a leading cause of property damage (in combination with flooding), loss of recreation space, and ecological damage around major urban areas and several inland lakes. In several places in the interior of the country - such as Rosario and Córdoba - the bodies of water have been contaminated to the point of affecting the work of the plants for their treatment.

We can take the case of Lake San Roque, the water supplier of the city of Córdoba, in the Province of Córdoba, it is a lake filled with organic matter, algae, viruses and bacteria, that is, it experiences the problem of eutrophication. There are projects to make treatment plants for the main towns, but the discharge continues to grow. No treatment system is working.

The Riachuelo-Matanza basin in the Province of Buenos Aires, with its 2,240 square kilometers and its three million inhabitants, of which only 45% have sewers and 65% have drinking water (1,700,000 people use cesspools or cameras septic), is one of the national symbols of pollution.

Three thousand companies dump their toxic or non-toxic solid or liquid waste every day and for years, without any type of treatment or with insufficient treatment. The pharmaceutical, chemical and petrochemical industries contribute 30% of the pollution, the alcoholic beverages industry and tanneries 3%. These rollovers are added sewage effluents. Altogether, it receives 368,000 cubic meters of industrial waste daily, no less than twice the average minimum flow of the river; This load constitutes a dangerous one that destroys each drop of water transforming it into an explosive drop of contamination. The Riachuelo mud has high concentrations of chromium, copper, mercury, zinc and lead. The highest concentrations of chromium and lead were found in the limits of the municipalities of Avellaneda and Lanús in the Province of Buenos Aires.

In urban and rural areas of the northwest of the Province of Buenos Aires, the Puelche aquifer –recognized as one of the largest in the world- presents different levels of contamination with nitrates and coliform bacteria. The top section burns in toxic garbage. The discharge is meteoric and the water can carry substances associated with manholes, landfills, and waste nitrates. The densely populated area of ​​the Buenos Aires suburbs, the Puelche water has nitrate concentrations up to three times higher than the permitted limits. The west channel of the municipalities Beriso and Ensenada, Province of Buenos Aires, languishes. In no case are the treatment plants enough, the treatments that companies should carry out before dumping them into the channels are between deficient and non-existent. All waste is lethal: heavy metals, organic and inorganic compounds.

On the other hand, the company “Aguas Argentinas” estimated that 2,300,000 m3 of untreated sewage flow –per day- into the Río de la Plata. To these are added 1,900,000 m3 per day of industrial discharges from the Buenos Aires Metropolitan Area. In the case of the Autonomous City of Buenos Aires, the main repercussion lies in the fact that environmental water quality standards constantly exceed the band of 300 continuous meters to the coast of the Río de la Plata, preventing recreational use (for unhealthy) of the beaches that were once so important to their inhabitants.
Most of the water consumed by the population comes from the same bodies into which sewage and industrial effluents are evacuated. Given the lack of treatment for them, the population ends up consuming drinking water of questionable quality or at a high cost of purification.

Groundwater pollution should be considered the most important pollution problem in Argentina, mainly due to the exposure to health risks of a large part of the households - including a large proportion of those with low resources - that They depend on groundwater for their daily needs.

The groundwater is not released from discharges because it is hidden underground, the most critical area is the Metropolitan of Buenos Aires, due to the large number of people affected and the low infrastructure coverage in the most remote municipalities. The main source of contamination is septic tanks and, to a lesser extent, industrial wastewater. The waters have bacteriological and saline contamination by nitrate.

The most effective solution is to promote the extension of sanitation and drinking water services to low-income neighborhoods and suburban areas that currently do not receive it.

Arsenic in water:

The presence of arsenic in water can be explained as a result of the use, sometimes excessive and uncontrolled, of products related to agricultural activities, gardening and cleaning of weeds, such as fungicides, insecticides and pesticides in general. Many of them have arsenic as a toxic compound, because its use is indicated to eradicate various pests.


The main routes of human exposure to arsenic are ingestion and inhalation. Arsenic accumulates in the body by chronic exposure and exceeding certain concentration levels. It can cause conditions such as skin alterations (relaxation of the cutaneous capillaries and their dilation), dermal lesions (skin neoplasms), peripheral vascular disease ("black foot disease"), as well as respiratory diseases; neurological (peripheral neuropathies), cardiovascular and various types of cancer (lung, corner, liver, bladder and skin).

In addition, people who ingest inorganic arsenic for a long time, via drinking water, may present palmoplantar hyperkeratosis, the main manifestation of which is skin pigmentation and calluses located on the palms of the hands and feet.

Some arsenic toxicity studies indicate that many of the current standards based on the WHO guidelines are very high, and raise the need to re-evaluate the limit values ​​based on epidemiological studies; for example, in Argentina it is estimated that the limit should be reduced from 0.05 mg / l to 0.01 mg / l. In other cases, these values ​​could be increased according to regional conditions. In Latin America it has been seen that at similar levels of arsenic in different conditions (weather, nutrition, and others) the level of damage is different.

The permanent ingestion of water contaminated by arsenic salts causes the so-called
Chronic endemic regional hydroarsenicism (HACRE), very common in many regions of the planet.

The origin of this disease is associated with the consumption of water with high concentrations of arsenic, together with the excessive heat in these areas. These two factors cause adults in these regions to contract irreversible injuries that incapacitate them for work, even occasionally causing death. The first symptoms usually appear between puberty and adulthood, although it can appear in school age.

We all know that water is an element and one of the most important needs for human beings; however, we continue to contaminate and waste it without any control.

The only way to reverse this process that is silently but inevitably deteriorating our living environment, contaminating our food and threatening the health of present and future generations, is through a plan to put an end to the dumping of substances into water. A radical change is necessary in the way in which the problem of pollution is faced and to demand that government agencies and industries hold the public accountable for the substances that are produced and released into the environment. As well as a progressive reduction in the generation of these pollutants. There would be two ways to do it ...

Management, management or control of pollution

They are systems that try to handle or manage pollution. It focuses on what happens at the “end of the pipe”, that is, once the waste has already been generated. It is based on the principle of assimilation, which considers that the environment is in a position to assimilate the pollutants it receives. The protection of each environment is based on requiring the different industries not to exceed certain emission levels of some pollutants. One of its consequences is the transfer of substances from one medium to another, but the total pollutant load in the environment does not decrease. To avoid exceeding the limits of substances in the effluents, it can be achieved that these remain in the treatment filters. If these filters are later incinerated or buried, the polluting substances will go into the atmosphere or contaminate the soil and underground water tables.

There are few, however, the substances covered, for most of the compounds there are not even standards. Nor do they take into account the simultaneous effect of all substances or the complexity of the composition of effluents and emissions, where a wide range of different pollutants cannot be adequately managed.

Contamination prevention

This approach, by accepting that once the polluting substances are generated, eliminating the risks associated with them is often impossible, promotes the prevention of that pollution from its origin, from its own source. It is necessary to avoid the generation of waste by applying clean technologies that do not use toxic materials or pose a risk to humans.

Instead of trying to control or manage discharges or investing in million-dollar effluent treatment systems, the progressive reduction in the generation of pollutants by reducing the use and production of waste solves the problem.

To start changing the process of generation and elimination of pollutants it is necessary:

-Provide financial mechanisms and facilitate credit lines that allow the replacement of the substances used and produced.

-Prohibit the production, import and use of dangerous products.

-Perform epidemiological investigations and on the levels of contaminants in water courses, food and breast milk, especially in the areas most affected by contamination.

-Establish a waste pollution prevention program that includes, among other points: the prevention of consumption and dumping of polluting products.

-Organize an information dissemination campaign, in collaboration with neighborhood organizations and consumers, aimed at avoiding the use of harmful substances in homes.

-Implement a plan for the replacement of disposable containers and the recovery of the organic fraction to produce compost.

-Give a complete tertiary treatment to sewage waste.

-Prohibit the discharge into the sewer system of industrial waste.


* Cristian Frers
Senior Technician in Environmental Management and Senior Technician in Social Communication


Video: Arsenic free drinking water (July 2021).