Core Viewpoint - The average blood lead level in children in China has decreased to approximately 20μg/L, but lead exposure remains a significant public health concern, particularly in low- and middle-income countries where levels are much higher, affecting cognitive development and overall health [1][3]. Group 1: Blood Lead Levels and Health Impacts - Recent studies indicate that even low levels of blood lead can increase risks of cognitive developmental disorders, attention deficits, ADHD, premature birth, and hypertension [1][3]. - An estimated 5.5 million premature deaths annually are attributed to lead poisoning, resulting in a global IQ score decline of 765 million points [1][3]. Group 2: Sources and Risks of Lead Exposure - The review analyzed 39 studies since 2000, revealing that living in industrial lead pollution hotspots, occupational exposure, and environmental factors significantly affect blood lead levels [3][4]. - In low- and middle-income countries, lead exposure risks are exacerbated by inadequate regulation, lack of awareness, and severe environmental pollution from lead-related industries [3][4]. Group 3: Recommendations for Future Research and Management - Future research should focus on the pathways of lead exposure from industrial pollution, contaminated food and spices, and the impact of lead-contaminated cookware on blood lead levels [4]. - Comprehensive lead risk management is necessary, including legislative measures to limit lead content, market monitoring, and community interventions [4].

Core Viewpoint - The recent lead poisoning incident in Gansu Tianshui has raised significant public concern regarding children's lead exposure and food safety, highlighting the need for improved monitoring and prevention measures [2][5]. Summary by Sections Incident Overview - A joint investigation in Tianshui revealed that staff at Peixin Kindergarten purchased lead-containing paint online, which was then used in food preparation. The police seized the remaining paint, which was marked as non-edible [2][5]. - As of July 7, 233 out of 251 children tested at the kindergarten showed abnormal blood lead levels, with two food samples exceeding the national safety standard for lead contamination [5][6]. Health Implications - Lead poisoning poses severe risks to children, with symptoms often being subtle and initially manifesting as irritability. Long-term exposure can lead to irreversible damage, particularly to the nervous system [2][6][7]. - The absorption rate of lead in children is significantly higher than in adults, making them more vulnerable to its harmful effects [6][7]. Sources of Lead Exposure - Common sources of lead exposure include lead-based paints, substandard toys, traditional food containers, and household dust. Food accounts for 47% of lead exposure, while indoor and outdoor dust contributes 45% [9][10]. - Recent trends indicate that lead poisoning cases are often linked to traditional remedies and practices, such as the use of lead-containing powders in certain regions [10][11]. Monitoring and Prevention - Active screening for blood lead levels is crucial, as many cases are identified through routine monitoring rather than symptomatic presentation [3][4]. - The World Health Organization recommends intervention when blood lead levels exceed 50 μg/L, with the CDC suggesting a threshold of 35 μg/L [13][14]. Treatment and Management - Treatment for lead poisoning includes removing the source of exposure, nutritional support, and, if necessary, chelation therapy under medical supervision [14][15]. - Regular follow-up is essential for children with elevated blood lead levels to monitor cognitive development and potential long-term effects [14][15].

Core Points - A kindergarten in Gansu, China, is under investigation due to multiple cases of lead poisoning among children, with 19 children hospitalized across provinces and over 200 samples sent for retesting [1] - Lead is identified as one of the three major heavy metal pollutants, posing significant health risks, especially to children, with the World Health Organization (WHO) stating that lead is the greatest environmental threat to children [2][4] - The ideal blood lead concentration in humans should be zero, as lead has no physiological function and can cause irreversible damage, particularly in children [4][5] Health Impact - Lead poisoning can lead to severe health consequences, including irreversible damage to organs and systems during childhood development, with potential long-term effects such as memory loss and intellectual disabilities [5][6] - Research indicates that for every 10 micrograms per liter increase in blood lead concentration, IQ can decrease by 0.25 to 0.5 points, and a 100 microgram per liter increase can result in a height reduction of 1 centimeter [6] Vulnerability of Children - Approximately one-third of children globally are affected by lead poisoning, with around 800 million children having blood lead levels at or above the warning threshold of 5 micrograms per deciliter; in China, this number is about 31.23 million [7] - Children are more susceptible to lead exposure due to their underdeveloped blood-brain barrier, higher absorption rates through the digestive system, and lower excretion capabilities compared to adults [7] Sources of Lead Exposure - The WHO estimates that the sources of lead exposure in children include indoor and outdoor dust (45%), food (47%), drinking water (6%), and air (1%) [8] - Common sources of lead contamination include traditional practices, such as using lead-containing materials in food preparation and folk remedies that incorporate lead compounds for medicinal purposes [9][10] - Food items, particularly those made using traditional methods or contaminated with lead-based pesticides, can also pose risks, although the primary concern is the "hand-to-mouth" route of exposure through toys and household items [10]