During the processing of olive oil, olives are crushed and mixed with water. The oil is then separated out from the dirty water and solid residue.
“The water used in the process and then discarded is often just pumped out onto surrounding land,” environment expert Marwan Dimashki told IRIN.
“This waste water contains polythenols which provide the natural green and black colouring of olives. However, they are chemicals which, when spread in large quantities, change environmental conditions and cause a reduction in soil fertility.”
Impact on human health
He said human health could be at risk. "Contaminated water becomes undrinkable. It goes brown and smelly and contains chemicals bad for human consumption, such as some of the polythenols."
Where processing plants are close to rivers, the waste water can run off into the rivers, harming aquatic life (with toxic chemicals or through compounds in the waste using up supplies of oxygen) and contaminating human drinking water.
If pomace - the solid residue left over from the processing of olive oil - is not properly dried out and disposed of, it too can seep into the soil, changing the acidity and nutrient make-up.
The impact on human health of consuming the chemicals in olive waste water is still unknown. Catechol, one of the chemicals in the waste water thought by some experts to be harmful, is not considered a threat by the World Health Organization (WHO).
"Catechol is not considered by WHO in its guidelines for drinking-water quality and thus there is no proposed drinking-water recommended maximum limit," said Bruce Gordon, head of the drinking water safety and quality team at WHO.
However, the International Agency for Research on Cancer (IARC) lists catechol as "possibly carcinogenic to humans".
The problem is not a small-scale one. Syria is the world’s fifth largest olive oil producer, contributing 4.6 percent of the world’s supply each year from its 920 mills.
The total waste water from Syria’s olive oil production amounts to 700,000 cubic metres a year, along with 280,000 tonnes of pomace.
Lack of awareness
The reasons for the contamination include dated technology and a lack of awareness by mill owners.
“The majority of the mills are family-run businesses which still use traditional presses rather than [modern] machinery,” Dimashki said. “They do not have the equipment to clean the waste water and often cannot afford to buy it.”
Apart from lacking the financial resources, many mill owners are unaware of the environmental damage they are causing. “There is a lack of education as to why and how waste products need to be dealt with, so mill owners release the waste water not realizing it will harm their land as well as the wider environment,” Dimashki said.
However, the importance of the olive oil industry means the problem is receiving attention. A 1.7 million euro three-year regional project to tackle the industry’s pollution across Syria, Lebanon and Jordan, funded by the UN Development Programme and the European Commission, concludes at the end of this year.
During the initial stages of the project, every olive mill was registered. Mill owners were given information on the negative effects of discharging waste water and on how they should treat it.
The owners were informed of the uses to which pomace could be put so they would not need to throw it away: It can be sold to factories which could extract the remaining oil for use in the manufacture of other products.
One of the mills to have benefited from the project is the Massalme Brothers Mill in Dar’a, southern Syria. The mill’s owners have learnt how to treat waste water and store it for collection, rather than discharging it onto surrounding land. Their mill’s pomace is dried and sold to factories in Aleppo where it is used to make the city’s famous olive oil soap.
The final stage of the project, due to begin in September, is the trial use of a mobile waste water treatment plant.
“Education is not enough,” Dimashki, who heads the project, said. “Not all the mill owners can afford modern machinery to treat their waste water… so the plant will move around the country cleaning the water.”
Demonstrations will start in Tartous on the Syrian coast, at one of the most polluting mills in the country.
Central treatment plants?
Given the huge demand for waste water treatment, experts say large central treatment plants will be needed in the future.
“Without this technology, the pollution from olive oil processing will lead to greater ecological problems,” said Roland Damann, head of Enviplan, the German environmental planning firm which supplied the mobile treatment plant.
“The environmental balance is getting more and more fragile over time so there is a long-term obligation to move the olive oil industry towards good ecological standards. Syria has started this and so must other countries,” he said.
Disclaimer:This material comes to you via IRIN, the humanitarian news and analysis service of the UN Office for the Coordination of Humanitarian Affairs. The opinions expressed do not necessarily reflect those of the United Nations or its Member States.
Photo: Copyright IRIN