Influence of Indoor Air Filtration Strategies on Occupant Health Indicators

NCT ID: NCT02769208

Last Updated: 2016-06-01

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: NA
• Total Enrollment: 89 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2014-11-30
• Study Completion Date: 2015-01-31

Brief Summary

The purpose of this study is to evaluate whether two different central air purification technologies reduce air pollutant exposure and beneficially influence health as evaluated with a suite of biological markers related to cardiovascular and respiratory disease risk.

Detailed Description

This study will test two common types of central air handling unit filtration technologies, high-efficiency particulate air (HEPA) filters and electrostatic precipitators (ESPs), to evaluate the impacts of these technologies on personal exposure to air pollutants and the associated cardiovascular and respiratory health outcomes. HEPA filters remove a high percentage of the particulate matter in the air, as do ESPs, but ESPs also generate ozone, which may have its own detrimental health effects. These air purification technologies will be placed in different combinations with a coarse pre-filter to protect the air exchange machinery (combinations: pre-filter only, pre-filter + HEPA, and pre-filter + HEPA + ESP) in both the residences and offices of study participants living on a factory campus in Changsha, Hunan Province, China. Large dormitories and office buildings with central air handling units are common in China and around the world, and so adding air purification into the central ducts represents a practical strategy to reducing personal exposure to air pollution and related health outcomes. The Changsha area commonly suffers from high air pollution, and the dormitories and offices on this workspace are already outfitted with both HEPA filters and ESPs. Therefore, testing these technologies in this environment presents a natural experimental condition to test the benefits of air purification. The study investigators hypothesize that both the pre-filter + HEPA and pre-filter + HEPA + ESP conditions will reduce particulate matter exposure and reduce biological markers of cardiovascular and respiratory disease compared to the pre-filter alone, but that the ESP will generate enough ozone to lead to lower health benefits than HEPA+pre-filter condition.

Conditions

Risk Factors for Respiratory and Cardiovascular Disease

Study Design

• Allocation Method: NON_RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: PREVENTION
• Blinding Strategy: SINGLE

Study Groups

Group A: Pre-Filter Only Intervention

Subjects in Group A start with baseline conditions of pre-filter + HEPA + ESP in their offices and dorms. After a baseline biological measurement, they then receive a 5-week intervention in which both the HEPA and ESP are removed, leaving only a pre-filter. This intervention period includes a biological measurement 2 weeks into the intervention and other 4-5 weeks into the intervention. The baseline air purification conditions are then restored, and another biological measurement is taken 2 weeks after that.

Group Type: ACTIVE_COMPARATOR

Central air handling unit air purification technologies

Intervention Type: DEVICE

As described in the arm descriptions, the interventions involve changing the baseline pre-filter + HEPA + ESP conditions by removing either just the ESP or both the ESP and the HEPA for a five week period.

Group B: Pre-filter + HEPA Intervention

Subjects in Group B start with baseline conditions of pre-filter + HEPA + ESP in their offices and dorms. After a baseline biological measurement, they then receive a 5-week intervention in which the ESP is removed, leaving a pre-filter + HEPA combination. This intervention period includes a biological measurement 2 weeks into the intervention and other 4-5 weeks into the intervention. The baseline air purification conditions are then restored, and another biological measurement is taken 2 weeks after that.

Group Type: ACTIVE_COMPARATOR

Central air handling unit air purification technologies

Intervention Type: DEVICE

As described in the arm descriptions, the interventions involve changing the baseline pre-filter + HEPA + ESP conditions by removing either just the ESP or both the ESP and the HEPA for a five week period.

Interventions

Central air handling unit air purification technologies

As described in the arm descriptions, the interventions involve changing the baseline pre-filter + HEPA + ESP conditions by removing either just the ESP or both the ESP and the HEPA for a five week period.

Intervention Type: DEVICE

Other Intervention Names

Pre-filter; HEPA filter; Electrostatic precipitator (ESP)

Eligibility Criteria

Inclusion Criteria

• Healthy adults;
• Live and work at the Broad Town work campus in eastern Changsha, Hunan Province, China

Exclusion Criteria

• Has any of the following diseases: chronic respiratory, cardiovascular, liver, renal, hematological disease; diabetes mellitus;
• Has any other diseases that may confound or complicate the effects of the intervention
• Pregnant females

• Minimum Eligible Age: 18 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

Duke University

OTHER

Sponsor Role: collaborator

Tsinghua University

OTHER

Sponsor Role: collaborator

Rutgers University

OTHER

Sponsor Role: collaborator

Feng Li

OTHER

Sponsor Role: lead

Responsible Party

Feng Li

Attending Physician

Responsibility Role: SPONSOR_INVESTIGATOR

Principal Investigators

Junfeng Zhang, PhD

Role: PRINCIPAL_INVESTIGATOR

Duke University

Yinping Zhang, PhD

Role: PRINCIPAL_INVESTIGATOR

Tsinghua University

Locations

Shanghai First People's Hospital

Shanghai, Shanghai Municipality, China

Countries

China

Other Identifiers

2014KY107

Identifier Type: -

Identifier Source: org_study_id