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Formaldehyde: Indoor Air Quality Pollutant and Testing

FORMALDEHYDE Cancer Warning

Formaldehyde Testing Dallas – Fort Worth

ScanTech offers selective testing of indoor formaldehyde testing in both residential and commercial buildings in the Dallas – Ft. Worth region.

http://www.indoorairqualitytestingdallas.com/

Formaldehyde (Chemical formula CH2O and also known as Methanal) is a colorless, water soluble gas at room temperature with a pungent, irritating odor at less than 1 part per million. (1 ppm – and detectable as low as 0.83 ppm) It is an inexpensive chemical with excellent bonding properties produced in high volume throughout the world. A major use is in the fabrication of urea-formaldehyde (UF) resins used primarily as adhesives when making plywood, particleboard and fiberboard. In the 1970’s it was a component of UF foam insulation in sidewalls until it was banned in 1982 by the U.S. Consumer Product Safety Commission because they found levels as high as 4 ppm. (but the ban was later overturned)

Due to it’s very low boiling point of -19 Celsius, formaldehyde is technically a VVOC (Very Volatile Organic Compound) and has very strong chemical and photo-chemical reactivity. It is commercially available as formalin which contains 38% formaldehyde and 6% – 15 % methanol.

Many common household cleaning agents contain formaldehyde and other sources include cigarette smoke and the combustion byproducts of gas / wood stoves and unvented space heaters such as kerosene heaters. It can also be found in paper products such as facial tissues, paper towels and grocery bags.

In general, emission or outgassing rates of formaldehyde increase with temperature, humidity, wood moisture content and decreased formaldehyde in the air. (due to passive diffusion) Generally, some remediation can be found by decreasing humidity and temperature, sealing materials with vinyl wallpaper or non-permeable paint and increasing ventilation. (air exchange rates)

Plywood is composed of several thin sheets of wood glued together with UF copolymeric resin which originally had a high HCHO to urea ratio of 1.5 to 1 to ensure adequate chemical cross-linking of all primary and secondary amino groups. Because the excess HCHO outgasses significantly and subsequently caused health complaints, this ratio was reduced to 1.05 to 1. Particleboard (compressed wood shavings mixed with UF resins at high temperatures) can emit formaldehyde continuously for comparatively long times; from several months to several years. Medium density fiberboard (MDF) was found to be the highest emitter of formaldehyde. Elevated levels are more likely to be found in newer homes with pressed wood materials such as flooring lumber mixed with the UF resin.

UF wood adhesives have excellent bonding performance, but are somewhat chemically unstable and release monomeric formaldehyde due to hydrolysis of the methyol end groups and sometimes the methylene bridges themselves. This means that hydrolytic decomposition and outgassing of HCHO is dependent on moisture levels, so UF-bonded wood products are primarily for indoor use where humidity levels are typically controlled.

Emissions do tend to decrease with time as the materials out-gas, age and cure. It is also used in the production of urea-formaldehyde foam insulation. (UFFI)

While there are several other sources of formaldehyde such as wood and forest fires, cigarette smoke, motor vehicle combustion, and decomposition of methane by sunlight and oxygen, etc. indoor levels are generally higher than outdoor levels. (10 – 20 parts per billion or 0.010 ppm – 0.020 ppm but may reach levels of 50 ppb in areas with significant photochemistry / smog )

Formaldehyde Molecule

Formaldehyde Molecule

Formaldehyde is also produced in the human body in small amounts as it is a metabolic byproduct of drinking alcohol (ethanol) among other chemical pathways. But the amount is relatively small and rapidly broken down into formic acid.

Individual sensitivity to formaldehyde varies, but from 10 – 20 % of the population appears to be highly sensitive to relatively low concentrations. This may be a result of TVOC (Total Volatile Organic Compound) synergy with other pollutants. The principle symptoms experienced are irritation of the eyes, nose, throat, dry facial skin and asthma like symptoms. (difficulty breathing, constriction of the bronchial tubes) Higher concentrations may even lead to headaches, fatigue, insomnia, nausea, unnatural thirst, menstrual irregularities, epistaxis, (nosebleed) coughing, chest / abdominal pain, and rapid heartbeat. (tachycardia)

Allergic dermatitis may occur from skin contact. There are also neurological-like symptoms in some, (including depression) with the chance of potential sensitization and even upper respiratory system cancers. There is some controversy about the cancer causing / carcinogenic effects with some evidence showing that risk only substantially increases at very high exposure levels such as in occupations which deal directly with formaldehyde such as embalmers and anatomists. But formaldehyde has been shown to be genotoxic in cell cultures which causes damage through DNA cross-linking, single strand breaks and chromosome aberrations which indicate that HCHO is mutagenic as well.

Regardless in testing, levels as low as 0.25 ppm (which is below the detectable odor threshold) significant eye and throat discomfort increases in frequency. Chronic bronchitis and asthma are more prevalent in children in homes with HCHO levels in the 0.06 – 0.12 ppm with a 22% decrement between the two values.

Pacemaker / Biomedical Implant Electromagnetic Interference EMI Sources & Issues

While pacemakers and other biomedical implants and implantable devices are somewhat more resistant to electromagnetic interference (EMI) than in previous generations, there are also more sources of potential EMI from new technologies such as hybrid vehicles, wireless chargers and so forth.

For example, the DC magnetic field from headphones can exceed 10 Gauss and can demonstrably interfere with the operation of a pacemaker. Cardiac centers a few years ago did a study and found that up to 15 % of patients with a pacemaker experienced interference issues when headphone came within 1.2 inches of the device, and up to 30 % of patients with an ICD (Implanted Cardioverter Defibrillator) also demonstrated operational abnormalities caused by the close proximity of the speaker.

While cell phones and MP3 players are less likely to cause issues, they should still be kept away from the heart / bioimplant area as there is a chance that RF energy from these electronic device could cause unpredictable behavior. Several years ago, there were some studies that indicated that MP3 players themselves (separate from the magnetic field of the speakers) could not affect a pacemaker, but since then MP3 players have evolved to other transmission modalities which involve using radiated Bluetooth frequencies.

Also, very recent studies (June 2015) have shown that cell phone can influence pacemakers in unexpected ways. At close range (within 6 inches) pacemakers can misinterpret the signal from a cell phone as a cardiac signal which then responds by consequently pausing the cardiac rhythm of the patient and could lead to fainting. For ICDs, the cell phone signal could be mistaken for ventricular tachyarrhythmia and lead to a painful shock as the ICD is programmed to respond to what it thinks is abnormal heart rhythm.

Also, high electric fields such as those beneath high voltage power lines could induce similar behavior if the implants are set to configurations which lower their EMI susceptibility.

Pacemaker ICD Diagram

Pacemaker ICD Diagram