Upon nearing the shoreline, one can immediately detect the briny scent of the sea. The salt carried in the air by the waves and wind leads to corrosion of exterior aluminum components due to chloride deposits. The impact of salt exposure extends beyond buildings near the coast, reaching more than 50 miles inland.
The reaction between unfinished aluminum and chloride ions causes rapid visible damage, weakening the structure of aluminum components with prolonged exposure. Industrial and urban coastal areas face heightened corrosion risks due to additional pollutants in the air.
To protect against salt spray corrosion, it is crucial to apply high-quality finishes to aluminum building components.
When selecting a finish for architectural aluminum in coastal regions, there are six key factors to consider:
1. Location
The elevated risk of corrosion for aluminum near the coast is attributed to the salt concentration in the air. Corrosion rates are influenced by factors such as temperature, wind, wave action, rainfall, humidity, and industrial pollution levels.
Given the fluctuating climate conditions near the ocean, it is essential to opt for the most durable finishes for aluminum components.
2. Fabrication
The design and fabrication of aluminum products play a crucial role in their response to salt spray in coastal areas. Attention should be paid to vulnerabilities at grain lines, fabricating flaws, seams, hems, and cut ends.
Prior to finishing, proper machining and shaping can help minimize the risks of corrosion. Components that hinder drainage and trap moisture should be avoided to prevent prolonged exposure to corrosive elements.
3. Paint Coatings
Paint coatings offer both a wide color range and robust protection for architectural aluminum. For enduring resistance against salt spray, opt for finishes containing 70% PVDF resin that meets industry standards like AAMA 2605.
AAMA 2605 compliant finishes showcase exceptional durability and UV resistance, undergoing rigorous testing, including exposure to salt spray. Testing in coastal areas confirms the longevity of these painted aluminum samples.
Received on September 20, 2020; Accepted on May 31, 2021; Published in 2021.
Open Access: This article is licensed under a Creative Commons Attribution 4.0 International License, permitting sharing, adaptation, distribution, and reproduction with proper credit given to the original author(s) and source. To view the full license, visit http://creativecommons.org/licenses/by/4.0/.
Abstract
Several cases have confirmed concerns about aluminum toxicity, linking it to neurotoxicity in patients with Alzheimer’s disease, epilepsy, and autism. Premature infants and individuals with renal failure face risks of CNS and bone toxicity from aluminum exposure through milk formulas, IV solutions, and vaccines. The use of antiperspirants further elevates human exposure to toxic aluminum. Further research is necessary to comprehend and address the consequences of aluminum overexposure.
Keywords: Aluminum, Toxicity, Environmental pollution, Alzheimer disease
Introduction
Aluminum, a highly conductive metal abundant in nature and released into the environment through natural weathering processes, can lead to health issues, including Alzheimer’s disease, with overexposure through ingestion and environmental sources. Elevated levels of aluminum in milk formulas and certain vaccines raise safety concerns. Antiperspirants also contribute to toxic aluminum exposure.
It is important to be aware of the sources of aluminum exposure in our daily lives. In addition to the aforementioned sources, aluminum can also be found in cooking utensils, baking powders, and even some medications. Avoiding using aluminum cookware and opting for alternatives like stainless steel or cast iron can help reduce exposure.
Some studies have suggested a link between aluminum exposure and a higher risk of developing Alzheimer’s disease. While more research is needed to fully understand this connection, it is prudent to limit unnecessary exposure to aluminum wherever possible.
Sources of aluminum
Aluminum sources can be natural (weathering, volcanoes) or anthropogenic. Acid rain plays a role in mobilizing aluminum in water, affecting plants and ecosystems. Some plants, like tea and certain vegetables, accumulate high aluminum levels, influenced by soil acidity and water quality.
Fig. 1.
The release of aluminum into the environment is exacerbated by acid rain.
Table 1.
Various food groups, including vegetables, fruits, roots, tubers, and seafood, contain significant levels of aluminum, influenced by soil acidity and plant diversity.
| Category of Food | Average Aluminum Content (mg/kg) |
|---|
| Beverages | $1.11 |
| Eggs | $1.52 |
| Milk and cheese | $3.05 |
| Fresh fruits | $6.84 |
| Potatoes and yams | $9.6 |
| Seafood | $11.9 |
| Vegetables | $16.8 |
There is a variety of beverages available, ranging from soft drinks and alcoholic drinks to certain fruit juices
Among dairy products, processed cheese with elevated levels of aluminum is not included
The presence of aluminum in the environment can be attributed to human actions. The release of aluminum into the air is heightened by various processes such as production, coal burning, mining, waste disposal, and vehicle emissions. Research indicates that both natural and human-related activities result in significant levels of aluminum in urban areas.
The level of aluminum in drinking water is dependent on its source and treatment methods. Aluminum salts are utilized in coagulation-flocculation processes to reduce turbidity. Many food items contain aluminum additives, including processed dairy products, breakfast cereals, flour, cakes, biscuits, baking powder, coffee, milk powder, table salt, bread, rice, and soft drinks. Aluminum additives are also used in food preservation and pickling processes.
Table 2.
Table 2 provides examples of food products containing aluminum additives and their respective functions
| Food | Aluminum compounds | Purpose |
|---|
| Types of Dairy Products | Sodium Aluminum Phosphate (basic) | Function of an Emulsifier |
The consumption of aluminum can occur through food, the use of aluminum cooking utensils, food packaging with aluminum foil, and storing food in aluminum cans. When cooking with aluminum utensils, especially with acidic foods, aluminum can leach into the food. Additionally, infants’ milk formula often contains high levels of aluminum. Seafood can also accumulate aluminum from polluted water sources. Other sources of aluminum exposure include toothpaste, vaccinations, antiperspirants, and certain medications.
Recent research has discovered elevated levels of aluminum in the brain tissue of individuals with Alzheimer’s disease, autism, and epilepsy.
In Camelford, UK, a mishap resulted in the erroneous discharge of 20 tons of aluminum sulfate into the water supply. This incident led to a high concentration of aluminum exposure and negative health effects on the population, such as decreased cognitive function and Alzheimer’s disease. Studies have linked increased aluminum levels in drinking water to neurodegenerative disorders.
Studies have demonstrated a link between high aluminum levels in drinking water and Alzheimer’s disease. The Camelford incident in 1988 caused severe health outcomes for those exposed, including memory loss, dysphasia, and hallucinations.
New studies by Mold et al. (2019b) have shown evidence of aluminum involvement in epilepsy. Another study by Mold et al. (2020) discovered heightened aluminum levels in donors with autism spectrum disorder, a condition often associated with autism and epilepsy. Furthermore, reports have shown aluminum contamination from the 1988 Camelford accident leading to health issues like Cerebral amyloid angiopathy (CAA). Exley and Vickers (2014) also reported a case of Alzheimer’s disease linked to aluminum exposure at the workplace. Mirza et al. (2017) identified high aluminum content in the brain tissue of patients with Alzheimer’s disease. Wang et al. (2016) established a connection between aluminum exposure and Alzheimer’s disease.
Infants are exposed to aluminum through infant formula and vaccinations. Studies indicate that formulas, especially soy-based ones, contain substantial levels of aluminum. Despite concerns raised by researchers, manufacturers have not taken steps to reduce aluminum content. Research recommends implementing mandatory regulations to lower aluminum levels in infant formulas due to potential health risks.
A recent study assessed aluminum levels in specialized infant formulas, revealing the highest levels in formulas for infants with poor weight gain and the lowest levels in formulas for infants with allergies and amino acid supplements. This suggests that reducing aluminum content in formulas may be achievable by identifying key ingredients.
While numerous studies have examined various infant formulas, few have focused on the impact of aluminum-contaminated formulas on infants’ health. Freundlich et al. (1985) documented cases of infants with renal failure and high brain aluminum concentration, despite not being exposed to any aluminum-containing agents. The study emphasized that milk formula was a significant source of aluminum and recommended lowering aluminum intake, particularly for infants with impaired renal function.
Aluminum compounds like aluminum hydroxides and aluminum phosphate are commonly used in vaccines as adjuvants to boost immune responses. However, they can cause minor allergic reactions at the injection site. Some studies have raised concerns about the elevated levels of aluminum in vaccines and the potential health hazards, particularly for infants and children. The transition from mercury to aluminum in vaccines has led to a substantial increase in aluminum exposure in infants over the past years. The CDC’s recommendation for pregnant women to receive vaccines containing aluminum in 2011 has sparked worries about fetal aluminum exposure.
Table 4 provides a visual representation of the aluminum contents in vaccines administered from birth to 18 months, highlighting the escalating exposure of infants to aluminum through vaccinations.