Sunday, October 20, 2013

The Effects of Dust on the Lungs

The lungs are protected by a series of defense mechanisms in different regions of the respiratory tract.
When a person breathes in, particles suspended in the air enter the nose, but not all of them reach the lungs. The nose is an efficient filter. Most large particles are stopped in it, until they are removed mechanically by blowing the nose or sneezing.
Some of the smaller particles succeed in passing through the nose to reach the windpipe and the dividing air tubes that lead to the lungs [more information about how particles entering the lungs].
These tubes are called bronchi and bronchioles. All of these airways are lined by cells. The mucus they produce catches most of the dust particles. Tiny hairs called cilia, covering the walls of the air tubes, move the mucus upward and out into the throat, where it is either coughed up and spat out, or swallowed.
The air reaches the tiny air sacs (alveoli) in the inner part of the lungs with any dust particles that avoided the defenses in the nose and airways. The air sacs are very important because through them, the body receives oxygen and releases carbon dioxide.
Dust that reaches the sacs and the lower part of the airways where there are no cilia is attacked by special cells called macrophages. These are extremely important for the defense of the lungs. They keep the air sacs clean. Macrophages virtually swallow the particles. Then the macrophages, in a way which is not well understood, reach the part of the airways that is covered by cilia. The wavelike motions of the cilia move the macrophages which contain dust to the throat, where they are spat out or swallowed.
Besides macrophages, the lungs have another system for the removal of dust. The lungs can react to the presence of germ-bearing particles by producing certain proteins. These proteins attach to particles to neutralize them.
Dusts are tiny solid particles scattered or suspended in the air. The particles are "inorganic" or "organic," depending on the source of the dust. Inorganic dusts can come from grinding metals or minerals such as rock or soil. Examples of inorganic dusts are silica, asbestos, and coal.
Organic dusts originate from plants or animals. An example of organic dust is dust that arises from handling grain. These dusts can contain a great number of substances. Aside from the vegetable or animal component, organic dusts may also contain fungi or microbes and the toxic substances given off by microbes. For example, histoplasmosis, psittacosis and Q Fever are diseases that people can get if they breathe in organic that are infected with a certain microorganisms.
Dusts can also come from organic chemicals (e.g., dyes, pesticides). However, in this OSH Answers document, we are only considering dust particles that cause fibrosis or allergic reactions in the lungs. We are not including chemical dusts that cause cancer or acute toxic effects, for example.

Reactions of the lungs to dust

The way the respiratory system responds to inhaled particles depends, to a great extent, on where the particle settles. For example, irritant dust that settles in the nose may lead to rhinitis, an inflammation of the mucous membrane. If the particle attacks the larger air passages, inflammation of the trachea (tracheitis) or the bronchi (bronchitis) may be seen.
The most significant reactions of the lung occur in the deepest parts of this organ.
Particles that evade elimination in the nose or throat tend to settle in the sacs or close to the end of the airways. But if the amount of dust is large, the macrophage system may fail. Dust particles and dust-containing macrophages collect in the lung tissues, causing injury to the lungs.
The amount of dust and the kinds of particles involved influence how serious the lung injury will be. For example, after the macrophages swallow silica particles, they die and give off toxic substances. These substances cause fibrous or scar tissue to form. This tissue is the body's normal way of repairing itself. However, in the case of crystalline silica so much fibrous tissue and scarring form that lung function can be impair. The general name for this condition for fibrous tissue formation and scarring is fibrosis. The particles which cause fibrosis or scarring are called fibrogenic. When fibrosis is caused by crystalline silica, the condition is called silicosis.
Factors influencing the effects of dustSeveral factors influence the effects of inhaled particles. Among these are some properties of the particles themselves. Particle size is usually the critical factor that determines where in the respiratory tract that particle may be deposited. Chemical composition is important because some substances, when in particle form, can destroy the cilia that the lungs use for the removal of particles. Cigarette smoking may alter the ability of the lungs to clear themselves.
Characteristics of the person inhaling particles can also influence the effects of dust. Breathing rates and smoking are among the most important. The settling of dust in the lungs increases with the length of time the breath is held and how deeply the breath is taken. Whether breathing is through the nose or mouth is also important.

 diseases of dusty operations

The classic diseases of "dusty" occupations may be on the decline, but they have not yet disappeared. Workers today still suffer from a variety of illnesses caused by dust they inhale in their work environments. For practical purposes, we limit this document to dust. We do not take into consideration combined effects arising from exposures to dusts, gases, fumes and vapours.
Some types of lung diseases caused by the inhalation of dust are called by the general term "pneumoconiosis." This simply means "dusty lung."
The changes which occur in the lungs vary with the different types of dust. For example, the injury caused by exposure to silica is marked by islands of scar tissue surrounded by normal lung tissue. Because the injured areas are separated from each other by normal tissue, the lungs do not completely lose their elasticity. In contrast, the scar tissue produced following exposure to asbestos, beryllium and cobalt completely covers the surfaces of the deep airways. The lungs become stiff and lose their elasticity.
Not all inhaled particles produce scar tissue. Dusts such as carbon and iron remain within macrophages until they die normally. The released particles are then taken in again by other macrophages. If the amount of dust overwhelms the macrophages, dust particles coat the inner walls of the airways without causing scarring, but only producing mild damage, or maybe none at all.
Some particles dissolve in the bloodstream. The blood then carries the substance around the body where it may affect the brain, kidneys and other organs.
The table below summarizes some of the most common lung diseases caused by dust.
The OSH Answers document Extrinsic Allergic Alveolitis has more information about diseases from exposure to organic dusts.

protecting the lungs from dust

To avoid respiratory or other problems caused by exposure to dust, hazardous substances should be substituted with non-hazardous substances. Where substitution is not possible, other engineering control methods should be introduced. Some examples are:
  • use of wet processes
  • enclosure of dust-producing processes under negative air pressure (slight vacuum compared to the air pressure outside the enclosure)
  • exhausting air containing dust through a collection system before emission to the atmosphere
  • use of vacuums instead of brooms
  • good housekeeping
  • efficient storage and transport
  • controlled disposal of dangerous waste
Use of personal protective equipment may be vital, but it should nevertheless be the last resort of protection. Personal protective equipment should not be a substitute for proper dust control and should be used only where dust control methods are not yet effective or are inadequate. Workers themselves, through education, must understand the need to avoid the risks of dust. A respiratory protection program is discussed in OSH Answers - Personal Protective Equipment under Respirator Selection and Respirator Care.

"More harm than good" from red grape antioxidant

A natural antioxidant found in red grapes, resveratrol, may not be as beneficial as previously thought. New research in older men suggests that it may counteract the benefits of cardiovascular exercise.
The study comes from researchers at the University of Copenhagen, who suggest that eating an antioxidant-rich diet may hinder the health benefits of exercise, such as lower blood pressure and cholesterol.
The researchers note that since aging is associated with impaired vascular functions due to oxidative strain, resveratrol - which has been shown to decrease vascular disease and improve cardiovascular health - was initially expected to improve cardiovascular health in older men. After all, it has been proven in animal studies to be of benefit in that department.
But in a surprise twist, the researchers found that unlike in our animal counterparts, resveratrol actually impairs the cardiovascular benefits of exercise in older men.
For 8 weeks, the researchers followed 27 men who were around 65 years of age and in good health. During that time, the men all took part in high-intensity exercise, but half of the men received 250 mg of resveratrol each day, while the other half received a placebo pill.
Lasse Gliemann, a researcher who worked on the study, explains the results and design of the experiment:

"The study design was double-blinded, thus neither the subjects nor the investigators knew which participant received either resveratrol or placebo."
"We found that exercise training was highly effective in improving cardiovascular health parameters, but resveratrol supplementation attenuated the positive effects of training on several parameters, including blood pressure, plasma lipid concentrations and maximal oxygen uptake."
So even though the men were gaining health benefits from exercising, the ones who took a daily dose of resveratrol saw many of these benefits effectively wiped out.
There have been several studies lately both lauding and denouncing the health benefits of resveratrol. A 2012 study, for example, shows resveratrol's potential as a therapy for diabetes, Alzheimer's disease and heart disease. Yet, another study from the same year reveals that the antioxidant may not benefit healthy women.
Though there are arguments for and against the compound found in red wine, this particular study from the University of Copenhagen suggests that "reactive oxygen species, generally thought of as causing aging and disease, may be a necessary signal that causes healthy adaptions in response to stresses like exercise."
In short, ingesting too many antioxidants may not be a good thing, but the researchers do say that the amount of resveratrol given to the men in the study exceeds what would normally be ingested through food alone.

Health Benefits of eating Mango

1.  Prevents Cancer:

Research has shown antioxidant compounds in mango fruit have been found to protect against colon, breast, leukemia and prostate cancers. These compounds include quercetin, isoquercitrin, astragalin, fisetin, gallic acid and methylgallat, as well as the abundant enzymes.

2.  Lowers Cholesterol:
The high levels of fiber, pectin and vitamin C help to lower serum cholesterol levels, specifically Low-Density Lipoprotein (the bad stuff)

3.  Clears the Skin:
Can be used both internally and externally for the skin. Mangos clear clogged pores and eliminate pimples. (Read more on page 5.)

4.  Eye Health:
One cup of sliced mangoes supplies 25 percent of the needed daily value of vitamin A, which promotes good eyesight and prevents night blindness and dry eyes.

5.  Alkalizes the Whole Body:
The tartaric acid, malic acid, and a trace of citric acid found in the fruit help to maintain the alkali reserve of the body.

6. Helps in Diabetes:
Mango leaves help normalize insulin levels in the blood.  The traditional home remedy involves boiling leaves in water, soaking through the night and then consuming the filtered decoction in the morning. Mango fruit also have a relatively low glycemic index (41-60) so moderate quantities will not spike your sugar levels.

7. Improved Sex:
Mangos are a great source of vitamin E. Even though the popular connection between sex drive and vitamin E was originally created by a mistaken generalization on rat studies, further research has shown balanced proper amounts (as from whole food) does help in this area.

8. Improves Digestion:

Papayas are not the only fruit that contain enzymes for breaking down protein. There are several fruits, including mangoes, which have this healthful quality. The fiber in mangos also helps digestion and elimination.

9. Remedy for Heat Stroke
Juicing the fruit from green mango and mixing with water and a sweetener helps to cool down the body and prevent harm to the body. From an ayurvedic viewpoint, the reason people often get diuretic and exhausted when visiting equatorial climates is because the strong “sun energy” is burning up your body, particularly the muscles.  The kidneys then become overloaded with the toxins from this process.

10. Boosts Immune system
The generous amounts of vitamin C and vitamin A in mangos, plus 25 different kinds of carotenoids keep your immune system healthy and strong.

Facts and trivia:

  • According to some, more mangos are eaten fresh than any other fruit in the world.
  • Originated 4,000 plus years ago.
  • Biologically a close relative with other flowering plants like cashew and pistachio.
  • Originated in sub-Himalayan plains.
  • In India where they are most heavily grown and eaten, mangos are known as “safeda.”
  • There are over 1,000 different varieties of mangos.

Plums nutrition facts

Wonderfully delicious and juicy plums are botanically belonging within the family of Rosaceae. The fruit is a drupe belonging to the genus: Prunus which also includes peaches, nectarine, almonds and damson. Scientific name: Prunus domestica.
The plant is best described as small tree or large shrub and widely cultivated in the United States, Europe, Japan and China. Many cultivars of plums are grown all over the world, which differ in their color, size and growing characteristics based upon their country of origin. Generally, each variety of the plum trees bears numerous, almost uniform sized fruits between May and September months.

Each berry is about the size of medium-sized tomato, measuring about 5-6 cm in diameter and weigh about 50-70 g. It has central depression at the stem side. Internally, the pulp is juicy and varies widely from creamy yellow, crimson, light-blue or light-green in color depending upon the cultivar type.
There is centrally placed single, smooth but hard stone-like seed. Seeds are inedible.
It has sweet and tart taste pulp with pleasant aroma. Some common cultivars of plums are: cherry plum, damson, blackthorn plum.

Health benefits of Plums

  • Delicious, fleshy, succulent plums are low in calories (46 calories per 100 g) and contain no saturated fats; however, contain numerous health promoting compounds, minerals and vitamins.
  • Certain health benefiting compounds present in the plum fruits, such as dietary fiber, sorbitol, and isatin are known to help regulate the functioning of the digestive system and thereby relieve constipation conditions.
  • Total antioxidant strength of plums measured in terms of ORAC (Oxygen radical absorbance capacity) is 6259 ┬Ámol TE/100 g. Fresh berries are a moderate source of vitamin C, which is also a powerful natural antioxidant. Consumption of foods rich in vitamin C helps the body develop resistance against infectious agents, counter inflammation and scavenge harmful free radicals.
  • Fresh plums, especially yellow Mirabelle type, are a moderate source of vitamin A and beta carotene. Vitamin A is essential for good eye sight. It is also required for maintaining healthy mucus membranes and skin. Consumption of natural fruits rich in vitamin A has found to protect from lung and oral cavity cancers.
  • The fruit is also good in health promoting flavonoid poly phenolic antioxidants such as lutein, cryptoxanthin and zea-xanthin in significant amounts. These compounds help act as scavengers against oxygen-derived free radicals and reactive oxygen species (ROS) that play a role in aging and various disease processes. Zea-xanthin, an important dietary carotenoid selectively absorbed into the retinal macula lutea where it is thought to provide antioxidant and protective UV light-filtering functions.
  • Plums are plentiful in minerals like potassium, fluoride and iron. Iron is required for red blood cell formation. Potassium is an important component of cell and body fluids that helps controlling heart rate and blood pressure.

  • In addition, the berries are moderate sources in B-complex groups of vitamins such as niacin, vitamin B-6 and pantothenic acid. These vitamins are acting as cofactors help the body metabolize carbohydrates, proteins and fats. They also provide about 5% RDA levels of vitamin K. Vitamin K is essential for many clotting factors function in the blood as well as in bone metabolism and help reduce Alzheimer's disease in the elderly.