**2. Material and methods**

*Solvents, Ionic Liquids and Solvent Effects*

methods [1].

In occupational settings where organic solvents are used or processed, prevention measures have to be established and followed. Their establishment should obey the general principles of prevention and also be based on chemical risk prevention

Among the main chemical substance families of organic solvents, we can distinguish the family of the halogenated hydrocarbon. The latter includes a subgroup named the chlorinated hydrocarbons. Since the 1920s, chlorinated hydrocarbons have been widely used for their stripping property. In fact, because they are nonflammable compounds, chlorinated solvents were used in degreasing, notably in the cleaning of clothes. However, since the 1970s, their use has declined steadily because of the grow-

Once in the human body, their effects are multiple. Some effects are common to all halogenated solvents, and others are distinct and specific to the solvent depending on toxicological proprieties [2]. The common effects include irritation mainly of the skin and mucous membranes (ocular and respiratory) and neurological disorders especially neurobehavioral difficulties. Many chlorinated solvents cause liver

ing awareness of their harmful effect on humans and the environment [2].

or kidney damages [2]. Ultimately, some of them can even induce cancers.

some cases can lead to groundwater contamination [2].

laboratories in the field of air and biomonitoring.

machines is going to take place [7].

aromatic solvents, etc.) [3].

In addition, the recent literature reports with certainty that several volatile organic solvents including the chlorinated ones are deemed to be harmful to the environment by contributing to the production of tropospheric ozone via photochemical reactions. This is consequently causing respiratory disorders for suffering from asthma or respiratory failure. Besides, due to their low solubility in water and their limited biodegradability, these solvents can also lead to soil pollution and in

Due to their potential hazardous properties, in recent years, the use of organic solvents in industry and laboratories has progressed considerably. The precaution instructions, which fall under what is called "green chemistry," led to the suspension or a significant limitation of some solvents (chlorinated solvents, glycol ethers,

The perchloroethylene (PCE) and trichloroethylene (TCE) are considered as the second and the third most used chlorinated solvents, respectively. One of the industrial sectors that are largely using these two solvents is the dry cleaning industry. Actually, PCE and TCE are currently well-known to induce many adverse health effects [2, 4–7]. However, in Tunisia, dry cleaners generally use them by dint of their important cleaning properties. In case of noncompliance with the standardized prevention and industrial hygiene measures, their consumption may lead to the contamination of the workplaces' atmospheres, especially nearby solvent handlers, which can lead to health quality degradation in case of long-term exposure. In this context, for the purpose of protection of solvent handlers' health, the control of the occupational exposure is obligatory in Tunisia according to Law 94-28 of 21 February 1994 [8] and Law No. 95-56 of 28 June 1995 [9]. However, the actual indoor air monitoring is almost absent; besides, there is a shortage of specialized

In contrast, for instance, in the United States and Japan, PCE is automatically removed if frequent and intense exposure is confirmed in the workplaces. In France, a national project of gradual cessation of its use in dry cleaning industry is ongoing. In 2013, the installation of new PCE dry cleaning machines is prohibited in buildings contiguous to dwellings [5]. In January 2022, the substitution of all PCE

Actually, the occupational exposure monitoring of chemical pollutants has an important place in today's strategies for chemical risk prevention [10]. Moreover, the technical advances in the analytical chemistry field have allowed the development of sufficiently sensitive techniques in order to detect pollutants in low concentrations.

**28**

### **2.1 Selection of the organic solvents**

Dry cleaning is clothes and textiles cleaning process that uses a solvent other than water. Most of the time, the conventional and common technique consumes chlorinated hydrocarbons, primarily PCE [7]. In the current study, we decided to also include TCE because it was traditionally used in dry cleaning. Even though TCE is no longer used in France since the 1960s [7], we suspect its presence in dry cleaners as it is not explicitly banned by law in Tunisia. Thus, considering its toxicity and proved carcinogenicity, we decided to monitor it as well.

These solvents incur serious adverse effects threatening the health of workers following chronic exposure [11, 12]. They are also proved to be carcinogenic and probably carcinogenic to humans, for TCE and PCE, respectively [13].

**Table** shows the main exposure routes of these two solvents and their health effects and carcinogenicity.

#### **2.2 Identification and selection of dry cleaning facilities**

In order to explore the exhaustive list of dry cleaning facilities in the city of Sfax, we contacted the Sfax Chamber of Commerce and Industry and the Regional Union of Industry, Commerce and Handicrafts in Sfax. However, they neither had sufficient information about this industrial sector nor an updated list.

Therefore, we decided to carry out a door-to-door canvassing in the study area. We only included facilities on a radius of 5 km from the city center. We excluded facilities using solvents other than TCE and PCE. Besides, we concomitantly requested their acceptance to participate in our study. After that, we randomly selected half number of the facilities who freely and voluntarily accepted to collaborate.

Afterward, information was collected using a questionnaire with the aim of:


#### **2.3 Indoor air measurements**

There are two sampling methods of gas and vapors: passive and active air monitoring of TCE and PCE [14–18]. In this study, we adopted the active sampling of vapors by pumping onto an activated charcoal tube [19, 20]. This method is suitable for the quantification of high exposure levels of air pollutants and of many chlorinated compounds simultaneously. It has also the advantage of allowing the control of sampling conditions (air flow rate and duration).


#### **Table 1.**

*The main exposure routes of trichloroethylene and perchloroethylene, and their adverse health effects due to chronic inhalation and carcinogenicity.*

In order to assess the exposure level of the workers, we chose the sampling mode according to the workers' mobility inside the workplace. A fixed monitoring station characterizing the workplace atmosphere was carried out when employees are working in a steady position. The sampling device is fixed near employees and at the level of their airways in order to measure the exposure level (**Figures 1** and **2**) [14, 21]. Elsewhere, a personal air sampling was carried out in the worker's breathing zone in order to quantify the individual exposure when the job task requires the worker's mobility (**Figure 3**) [14, 21]. Samples were taken in the middle of the week for each facility (from Wednesday to Friday).

The sampling device consists of an activated charcoal sorbent tube with two sorbent sections (SKC® tube 226-16) [22]. The tube is connected by a flexible hose to a sampling pump: pocket pump (SKC® 210-1002 TX). The sampling takes place at a regular rate of 100 (±5%) cm3 /min for a 4-h shift (**Figures 1** and **2**). So, the indoor air is pumped out through two sorbent layers that are separated with foam and glass wool (800 and 200 mg). The first one is the sampling section and the second is a backup section that detects sample breakthrough [21].

After sampling, the sorbent tubes were stored in unpolluted areas at 4°C. Even though it is possible to store them at ambient temperature [20, 21] (limited to 8 days for PCE [19]), we preferred to avoid any minimal loss [17].

**31**

**2.4 Sample analysis**

*Active air monitoring using personal sampling.*

**Figure 2.**

**Figure 1.**

stirred for 30 min to promote desorption [19, 20].

*Per- and Trichloroethylene Air Monitoring in Dry Cleaners in the City of Sfax (Tunisia)*

Desorption of both solvents from activated charcoal was achieved using carbon disulfide. In fact, after breaking the tube glass tips, the content was put in a glass flask already placed in an ice bath to avoid any vaporization. Then, the content was

After the separation of the organic phase using filtration, it was directly injected (1 μL) and analyzed by gas chromatography with flame ionization detector (GC-FID). The used instrument is a SHIMADZU® chromatograph GC-2014. The capillary

*DOI: http://dx.doi.org/10.5772/intechopen.86725*

*Active air monitoring using fixed sampling station.*

*Per- and Trichloroethylene Air Monitoring in Dry Cleaners in the City of Sfax (Tunisia) DOI: http://dx.doi.org/10.5772/intechopen.86725*

**Figure 1.** *Active air monitoring using fixed sampling station.*

*Solvents, Ionic Liquids and Solvent Effects*

Main exposure route

Reported effects: chronic exposure via inhalation [11, 12, 25, 26]

IARC classification: cancer site [13, 38]

**Table 1.**

[11, 12]

In order to assess the exposure level of the workers, we chose the sampling mode according to the workers' mobility inside the workplace. A fixed monitoring station characterizing the workplace atmosphere was carried out when employees are working in a steady position. The sampling device is fixed near employees and at the level of their airways in order to measure the exposure level (**Figures 1** and **2**) [14, 21]. Elsewhere, a personal air sampling was carried out in the worker's breathing zone in order to quantify the individual exposure when the job task requires the worker's mobility (**Figure 3**) [14, 21]. Samples were taken in the middle of the week

*The main exposure routes of trichloroethylene and perchloroethylene, and their adverse health effects due to* 

**Solvents Trichloroethylene (TCE) Perchloroethylene (PCE)**

General population: inhalation and ingestion: depending on the

Occupational exposure: inhalation

○ Neurobehavioral difficulties

○ Respiratory hypersensitivity and pulmonary edema ○ Respiratory irritation

○ Subclinical liver effects

○ Risk of hypertensive endstage renal disease ○ Increase in kidney markers

○ Probably carcinogenic to humans: urinary bladder

exposure media

• Ocular effects ○ Irritation • Respiratory effects

• Hepatic effects

• Renal effects

• Group 2A:

• Neurological effects:

○ Visual alterations

General population: inhalation, ingestion, and dermal contact: depending on the

Occupational exposure: inhalation and/or dermal contact depending on the job process

exposure media

• Neurological effects:

○ Neuropsychic disorders ○ Neuromotor function alteration

○ Cranial nerve damage ○ Risk of Parkinson's disease

○ Liver damage and diseases • Immunological and lymphoreticular

○ TCE hypersensitivity syndrome ○ Immune system alterations ○ Autoimmune disease: Scleroderma

○ Anorexia, nausea, and vomiting

○ Carcinogenic to humans (kidney) • Limited evidence in humans: leukemia and/or lymphoma and liver

• Developmental effects: • Risk of congenital heart defects

• Gastrointestinal effects:

• Hepatic effects:

effects:

• Group 1:

*IARC: International agency for research on cancer.*

*chronic inhalation and carcinogenicity.*

The sampling device consists of an activated charcoal sorbent tube with two sorbent sections (SKC® tube 226-16) [22]. The tube is connected by a flexible hose to a sampling pump: pocket pump (SKC® 210-1002 TX). The sampling takes place at

air is pumped out through two sorbent layers that are separated with foam and glass wool (800 and 200 mg). The first one is the sampling section and the second is a

After sampling, the sorbent tubes were stored in unpolluted areas at 4°C. Even though it is possible to store them at ambient temperature [20, 21] (limited to 8 days

/min for a 4-h shift (**Figures 1** and **2**). So, the indoor

for each facility (from Wednesday to Friday).

backup section that detects sample breakthrough [21].

for PCE [19]), we preferred to avoid any minimal loss [17].

a regular rate of 100 (±5%) cm3

**30**

**Figure 2.** *Active air monitoring using personal sampling.*
